---
name: outdoor-gear-selection-guide
description: |
  Provides category-by-category outdoor gear selection criteria for hiking, camping, cycling, and general outdoor recreation. Covers footwear, layering systems, packs, shelter, and navigation with fit testing guidelines, durability priorities by use intensity, and budget tier recommendations.
  Use when the user asks about choosing outdoor gear, comparing hiking boots, selecting a backpack, building a layering system, or evaluating gear quality and durability.
  Do NOT use for specific brand or product recommendations, professional mountaineering equipment, cycling-specific gear (use cycling-route-planner), or fishing, hunting, or water sports equipment.
license: Apache-2.0
metadata:
  author: foundry-skills
  version: "1.0.0"
  tags: "research checklist guide analysis"
  category: "hobbies-crafts"
  subcategory: "outdoor-recreation"
  depends: ""
  disclaimer: "none"
  difficulty: "beginner"
---
# Outdoor Gear Selection Guide

## When to Use

**Use this skill when:**
- User asks how to choose hiking boots, trail runners, or approach shoes for a specific terrain or activity type
- User wants to understand how to build or optimize a layering system for a specific climate zone or season
- User needs to select a backpack by volume, frame type, torso length, or load type
- User asks about tent selection, sleeping bag temperature ratings, or sleeping pad R-values for a planned trip
- User wants to evaluate gear durability for their use frequency, or prioritize purchases across a limited budget
- User is building a complete outdoor gear kit from scratch for day hiking, overnight backpacking, or car camping
- User asks how to interpret gear specifications such as denier ratings, fill power, waterproof ratings (hydrostatic head), or insulation weight
- User is transitioning between activity levels -- car camping to backpacking, day hiking to overnight, or occasional to frequent use

**Do NOT use when:**
- User asks for specific brand or product names -- provide category criteria, specifications, and selection frameworks only
- User needs professional mountaineering, technical ice climbing, or glacial travel equipment (ropes, crampons, ice axes, harnesses, belay devices)
- User asks about cycling-specific gear such as helmets, cycling shoes, or bike-mounted bags (use `cycling-route-planner`)
- User needs fishing, hunting, or water sports equipment -- these have specialized safety and regulatory considerations outside this skill's scope
- User asks about gear repair, field modification, or seam sealing -- these are maintenance topics outside this selection framework
- User asks about vehicle-based overlanding or car-specific camping setups, which involve different weight and space constraints
- User needs gear for organized racing, competitive fastpacking, or ultra-distance events where sport-specific regulations apply

---

## Process

### Step 1: Establish the Gear Profile

Before recommending any category, collect four parameters that drive every decision downstream. Do not skip this step -- guessing leads to mismatched recommendations.

- **Primary activity type:** Day hiking on established trails, day hiking on off-trail or scrambling terrain, overnight backpacking (1-3 nights), extended backpacking (4+ nights), or car camping with no carry distance. Each changes weight priorities fundamentally.
- **Climate and terrain:** Ask for the specific geographic region or describe conditions: temperature range (daytime high and overnight low), precipitation type (rain, snow, mixed), altitude range, and terrain character (groomed trail, rocky, stream crossings, exposed ridgeline). Appalachian conditions differ from Sierra Nevada conditions which differ from Cascade conditions.
- **Use frequency:** Occasional (under 25 trips/year, or under 100 miles/year on foot), regular (25-50 trips/year, 100-300 miles/year), or frequent (50+ trips/year, 300+ miles/year). This determines how aggressively to weight durability over cost.
- **Budget tier:** Budget ($0-300 for a full kit), mid-range ($300-800 for a full kit), or premium ($800+ for a full kit). Individual category prices scale accordingly. Always confirm whether this is a per-category budget or a total kit budget.
- **Body and fit constraints:** Height, weight, and any known fit issues (wide feet, long torso, short torso, narrow shoulders) dramatically affect which categories require in-person fitting versus online purchase.

---

### Step 2: Evaluate and Specify Footwear

Footwear is the highest-stakes single gear decision. Wrong footwear causes blisters, ankle sprains, knee stress, and trail-ending discomfort. Every footwear recommendation must include construction details, not just category names.

- **Activity-to-footwear matrix:**
  - Groomed trail day hiking, light pack (under 20 lbs): trail runners with 4-6mm lug depth (faster break-in, lighter, cooler)
  - Rocky trail day hiking, uneven footing: low-cut to mid-cut hiking shoes with rubber rand and a stiffer midsole (torsional rigidity reduces foot fatigue)
  - Overnight backpacking with pack weights 25-40 lbs: mid-cut boot with firm midsole (Shore A hardness ~55-65) and ankle collar height of at least 4 inches above the footbed
  - Multi-day backpacking 40-55+ lbs: high-cut backpacking boot with a full-length, close-to-rigid midsole (Vibram MegaGrip or equivalent rubber compound); resoleable construction extends life significantly at 300+ miles of hard use
  - Off-trail scrambling or approach climbing: approach shoe with sticky rubber (smearing capability on rock slabs), low profile, downturned last

- **Midsole stiffness as a measurable criterion:** Request a twist test in the store. A day hiking shoe should flex somewhat along its length -- a multi-day backpacking boot should not flex along its length at all when twisted by hand. Excessive flexibility under load causes arch fatigue and knee tracking issues.

- **Fit testing protocol (in-store, non-negotiable for new buyers):**
  - Try on in the afternoon -- foot volume increases 5-8% over the course of a day due to fluid redistribution
  - Wear the exact socks you plan to hike in (merino wool, crew height, 15-18% nylon blend for durability)
  - With foot pressed to the front, fit one finger (not thumb) snugly behind the heel -- this is the standard 10-12mm heel-to-counter clearance
  - On a tilted fitting ramp or incline (most specialty outdoor retailers have one), walk downhill: toes should not strike the toebox. One to two millimeters of clearance at the front on a downhill angle prevents black toenails on descents
  - Stand on the edge of a step with the ball of the foot and let the heel drop: the boot should not allow heel lift more than 5-7mm. Excessive heel lift causes blisters at the heel cup
  - Walk for a minimum of 10 minutes on a hard surface. Pressure points that develop within 5 minutes will become blisters within 3 miles on trail

- **Material construction trade-offs with real durability thresholds:**
  - Full-grain leather: 800-1500+ mile lifespan, heaviest (1,400-2,000g per pair), 30-100 hour break-in, excellent waterproof longevity with regular wax treatment, repairable
  - Split-grain leather with synthetic panels: 500-800 mile lifespan, moderate weight (900-1,300g), 5-15 hour break-in, moderate water resistance
  - Synthetic mesh upper: 300-500 mile lifespan, lightest (600-900g), near-zero break-in, poorest water resistance, best breathability in heat
  - Waterproof membrane lining (ePTFE laminate construction): adds 100-150g, extends waterproofing to approximately 2-3 seasons of wet-weather use before delamination becomes a concern. Trade-off: reduces breathability by 30-40% measured in moisture vapor transmission rate (MVTR). Do not recommend for hot, dry climates.

- **Lug depth and traction by terrain:**
  - 3-4mm lugs: groomed gravel trails, packed dirt -- low rolling resistance, fast wearing
  - 5-6mm lugs: standard mixed trail -- optimal all-around depth
  - 7-9mm lugs: muddy, loose, or rooted terrain -- self-cleaning tread pattern important (spacing between lugs matters as much as depth)
  - Multi-directional lug pattern preferred over directional-only for off-trail use

---

### Step 3: Build the Layering System with Quantified Specifications

The three-layer system is not a suggestion -- it is a thermal management architecture. Each layer has a measurable, specific function.

- **Base layer (moisture transport layer):**
  - Function: Wick sweat away from skin surface to prevent evaporative cooling during rest stops and maintain dry skin contact
  - Merino wool: natural crimp fiber structure creates capillary action; odor-resistant due to lanolin content and fiber diameter (17-19 micron superfine resists bacterial colonization); thermal regulation effective across 35-85°F; slower drying than synthetics (30-45 minutes vs. 10-15 minutes for polyester)
  - Synthetic polyester: 100-150g/m² for lightweight, 170-200g/m² for midweight; dries 60-70% faster than merino; retains odor after 2-3 days of use; lower cost by 30-50%; maintains performance when wet
  - Weight categories: lightweight base (100-130g/m², for 60°F+), midweight (160-190g/m², 35-60°F), expedition-weight (220-260g/m², below 35°F)
  - ABSOLUTE RULE: Cotton absorbs 7x its weight in water, loses nearly all insulating value when wet, and dries extremely slowly. Cotton base layers in cold/wet conditions are a documented contributor to hypothermia. This is not preference -- it is a safety rule.

- **Mid layer (insulation layer):**
  - Function: Trap dead air to retain body heat. Measured in CLO units (1 CLO = thermal resistance maintaining a resting adult at comfort in 70°F). Target 1-2 CLO for the combined system in cold conditions.
  - Fleece (polyester pile): 100-weight fleece (thin, packable, 200-300g), 200-weight fleece (standard midlayer, 350-450g), 300-weight fleece (heavy, warm, bulky). Breathes well during high-output activity, dries fast, loses loft when compressed.
  - Down insulation: Fill power rating measures loft per ounce (600 fill = adequate, 700 fill = good, 800+ fill = premium backpacking grade, 900 fill = expedition). Higher fill power means same warmth at lower weight. Critical failure mode: down insulation loses 80-90% of insulating value when wet and is extremely slow to dry. Never rely on down as the sole mid layer in wet or humid conditions.
  - Synthetic insulation: PrimaLoft-style continuous filament or short-fiber constructions. Retains 60-80% insulating value when wet (compared to 10-20% for down). Heavier and bulkier than equivalent-warmth down by 15-25%. Lower cost by 30-50%. Preferred for consistently wet climates.
  - Midlayer selection rule: if the user will be in conditions with precipitation probability above 30%, recommend synthetic insulation or fleece, not down, as the mid layer.

- **Outer layer (shell layer):**
  - Function: Block wind and repel precipitation while allowing some moisture vapor to escape
  - Waterproof rating measured in hydrostatic head (HH): 5,000mm HH = light rain resistance, 10,000mm HH = moderate rain, 20,000mm HH = sustained heavy rain. For hiking in a rainy climate, 10,000mm HH minimum.
  - Breathability measured in MVTR (moisture vapor transmission rate): 5,000 g/m²/24hr = minimal breathability, 15,000-20,000 g/m²/24hr = good breathability, 30,000+ g/m²/24hr = premium (active hiking standard)
  - Hardshell: fully waterproof (15,000-30,000mm HH), seam-taped, ePTFE or similar membrane. Ideal for sustained rain or high-wind exposed conditions. Packable versions weigh 300-500g.
  - Softshell: DWR-treated face fabric only (typically 3,000-5,000mm HH), no seam taping. Breathable and stretch-friendly for high-activity use in light precipitation. Not suitable for sustained rain.
  - Insulated shell (3-in-1 system): combines shell and insulation layer. Versatile but makes mid-activity temperature regulation harder. Good for car camping or low-intensity use.
  - DWR (durable water repellency) treatment: the outer face fabric's ability to bead water. Degrades with use and washing. Restore with low heat (tumble dry or iron on low through a cloth) -- heat reactivates DWR chemistry. Rewash with DWR-restoring wash product when beading stops entirely.

- **Layering combinations by condition:**
  - Active hiking above 50°F: base layer only; mid and outer in pack
  - Active hiking 35-50°F: base + fleece or light synthetic; shell in pack
  - Active hiking 20-35°F: base + fleece + hardshell worn; extra mid layer in pack
  - Camp conditions at 20-35°F: all three layers + a camp-specific puffy (down or heavy synthetic jacket) worn only at rest -- do not hike in down or heavy synthetic as primary active layer
  - Wind and rain at any temperature: add 15-20°F of felt-cold penalty for sustained wind (windchill effect is real and dangerous)

---

### Step 4: Select Pack Volume and Fit System

Pack selection is a direct function of trip duration and base weight philosophy. Over-volumed packs are a documented cause of over-packing; under-volumed packs cause dangerous attachment of gear to the outside.

- **Volume-to-trip-type mapping:**
  - 10-20 liters: ultralight day hiking with minimal kit (water, snack, emergency layer, phone, first aid)
  - 20-30 liters: standard day hiking (full day kit for 5-10 miles, including 2L water, food, rain jacket, mid layer, first aid, headlamp, trekking poles in external loops)
  - 30-45 liters: fast-and-light overnight with ultralight sleeping system and tarp, or heavily curated 2-day kit
  - 45-55 liters: standard 1-3 night backpacking with conventional gear (3-person tent solo, standard sleeping bag, foam pad or inflatable pad)
  - 55-70 liters: extended 4-7 night trips, shoulder-season with extra insulation, or beginner backpacker with standard-weight gear
  - 70-85 liters: winter backpacking, group gear carry (bear canister required in some wilderness areas = 650-900 cubic inch dedicated space), or crew resupply
  - Beyond 85 liters: generally only justified for extended remote expedition use. Flag this as a niche category.

- **Torso length measurement (mandatory for packs over 40 liters):**
  - Have the user tilt their head forward -- the most prominent vertebra at the base of the neck is C7, the top measurement point
  - Place hands on the tops of the iliac crests (hip bones) with thumbs pointing back -- the thumbs meet at approximately L4/L5, the bottom measurement point
  - Measure the straight-line distance between these two points: this is torso length
  - Small: 15-17 inches, Medium: 17-19 inches, Large: 19-21 inches, Extra-Large: 21+ inches. Note: women's-specific fit packs have a shorter torso range and curved shoulder straps -- recommend for users with torso under 17 inches or shoulder widths under 15 inches.

- **Hip belt position is the single most important comfort factor:**
  - The padded portion of the hip belt must sit on top of the iliac crests, centered with the buckle at the navel line
  - A belt sitting on the waist (too high) creates rib compression and does not transfer load properly
  - A belt sitting below the hip crests transfers zero load from the pack to the hips
  - At proper position with a correctly loaded pack, hips should carry 70-85% of pack weight; shoulders carry the remainder
  - Test: load pack to 25-30% of body weight. If shoulder straps are bearing most of the load after hip belt is cinched, the torso length is too long.

- **Frame type selection:**
  - Frameless: under 30 liters for day packs, ultralight overnight with very light loads (under 15 lbs). No load transfer capability.
  - Flexible stay frame: packs 30-55 liters. Bent aluminum stays (usually two J-shaped) transfer some load to hip belt. Can be removed for air travel.
  - Rigid internal frame: packs 55+ liters. Provides full load transfer, maintains structure under heavy load (30+ lbs), adds 300-500g.
  - External frame: rarely recommended for modern hiking -- bulky, snags vegetation, poor center of gravity on steep terrain. Limited to specific high-load, low-terrain contexts.

- **Pack load testing before purchase:**
  - Load the pack with 20-25 lbs using stuff sacks or gear from the store (most specialty retailers will allow this)
  - Walk for 10-15 minutes, including stairs if available
  - Check for: hot spots at hip bones (padding too thin or belt too narrow), shoulder strap gap behind the shoulder (torso too short), load lifter straps pulling at more than 45 degrees (torso too long), lateral sway during walking (hip belt too wide or not cinched)

---

### Step 5: Specify Shelter with Technical Ratings

Shelter selection involves quantified specifications that directly determine safety margins. Generic "3-season tent" recommendations are insufficient without weight and weather-resistance numbers.

- **Tent construction types with real trade-offs:**
  - Freestanding double-wall dome: two poles crossing at the center, inner tent and separate rain fly creating an air gap for condensation management. Setup time 5-8 minutes. Works on rocky or snow surfaces where stakes are not possible. Weight range 3-6 lbs for 2-person options. Most forgiving for beginners.
  - Semi-freestanding: single crossing pole plus separate ridgeline, requires 2-3 stakes at each end for full tension. Lighter than freestanding (2.5-4.5 lbs), superior weather shedding from steep wall angle, needs good stake-able ground.
  - Single-wall ultralight (tarp or cuben fiber/Dyneema designs): lightest possible (0.8-2 lbs for 1 person), requires excellent setup skill and good trekking pole placement. Higher condensation exposure. Recommended only for experienced backpackers prioritizing pack weight.
  - Bivy sack: waterproof, breathable envelope around sleeping bag. Not a tent replacement -- offers no gear storage and extreme condensation issues in cold conditions. Emergency use or ultralight racing applications only.

- **Season ratings decoded:**
  - 3-season: handles sustained rain, 20-30 mph wind gusts, temperatures above freezing. NOT designed for snow load. 1,200-3,000mm HH on fly fabric, 1,500-5,000mm on floor.
  - 3+ season (extended season or "convertible"): reinforced pole structure for 30-40 mph wind, steeper walls shed light snow accumulation, heavier. Good choice for shoulder-season alpine trips.
  - 4-season: geodesic or semi-geodesic pole crossing pattern, 3+ poles on a 2-person tent, rated for 50+ mph wind and sustained snow load. Overkill for any non-winter use; noticeably heavier (5-8 lbs). Floor HH typically 5,000-10,000mm.

- **Capacity sizing rule (apply consistently):**
  - Tent rated capacity is based on shoulder-to-shoulder sleeping with no gear inside. For comfortable camping with gear storage, select capacity one person above actual occupancy.
  - 2-person tent for 1 person: gear and boot storage, elbow room
  - 3-person tent for 2 people: comfortable for couples, gear storage, dog accommodation
  - Do NOT size down to reduce weight at the cost of usable interior space -- moisture and condensation are managed by volume, not just membrane rating

- **Backpacking weight budget for shelter:**
  - Ultralight target: under 2 lbs total (fly + poles + stakes) per person
  - Standard backpacking target: under 3 lbs per person
  - Comfort backpacking (car camping distance, heavily developed sites): up to 4-5 lbs per person is acceptable

- **Sleeping bag temperature rating system:**
  - EN 13537 / ISO 23537 standard provides four ratings: Upper Limit (too warm), Comfort (woman sleeping), Lower Limit (man sleeping), Extreme (survival only)
  - The "comfort" rating for women and "lower limit" for men are the usable references. The "extreme" rating indicates survival risk, not comfort.
  - Add 10-15°F of cold buffer to the expected overnight low to determine the target comfort rating. A trip with 40°F overnight lows requires a sleeping bag rated to 25-30°F.
  - For backpacking, down bags offer the best warmth-to-weight ratio. Synthetic bags are preferred in wet conditions (Pacific Northwest, Appalachian spring).
  - Down fill power thresholds for sleeping bags: 550-650 fill = entry-level, 700-750 fill = mid-range (good balance), 800-850 fill = premium, 900+ fill = expedition-grade.

- **Sleeping pad R-value (insulation from ground):**
  - ASTM F3340-18 is the standardized R-value test for sleeping pads. Higher R-value = more insulation from cold ground.
  - Ground temperature is always lower than air temperature. Cold ground conducts heat away from the body more aggressively than cold air.
  - R-value guidelines: R-1 to R-2 (summer, temps above 50°F), R-2 to R-3.5 (3-season use, 25-50°F), R-4 to R-5 (winter and cold conditions, below 25°F), R-5+ (snow camping, sub-0°F)
  - Foam pad (closed-cell): reliable, cheap ($15-40), bomber durability, cannot be punctured, R-2 to R-4. Heavy and bulky to pack. Double as a pack framesheet in ultralight setups.
  - Inflatable pad: lighter (400-700g), compressible, higher R-value options (up to R-8) available, $70-250+. Puncture risk is real -- always carry a repair kit.
  - Combination (foam + inflatable stacked): used in winter or snow camping to achieve R-6+ at manageable cost.

---

### Step 6: Specify Navigation Tools with Realistic Failure Modes

Navigation is a safety system, not a convenience feature. Every navigation recommendation must address failure modes and redundancy.

- **Topographic map reading fundamentals apply regardless of tool choice:**
  - Contour interval (the elevation change between lines): standard USGS 7.5-minute quadrangle maps use 40-foot contour intervals. Closely spaced contours = steep terrain. This information cannot be replicated by a trail description.
  - Map datum: most digital mapping uses WGS 84 datum. Most USGS paper maps use NAD 27. A coordinate entered in the wrong datum can be off by 100-300 meters.
  - Magnetic declination: the difference between true north and magnetic north. In the eastern US, declination is approximately 10-15 degrees west. In the western US, 12-18 degrees east. Failure to account for declination when navigating with a compass introduces a systematic error of 200-300 feet per mile.

- **Navigation tool categories:**
  - Dedicated handheld GPS: 12-20 hour battery life on AA batteries (field-replaceable), operating temperature range typically -4°F to 158°F, 1-3 meter accuracy under open sky, pre-loadable topo maps, no cell signal dependence. Best for remote overnight and extended trips.
  - Phone with offline map application: convenient, 3-6 hour GPS battery drain (faster in cold), not water-rated without a case, battery fails below approximately 32°F (lithium-ion loses 20-40% capacity near freezing), 2-5 meter accuracy. Requires downloading map tiles before reaching the trailhead. 10,000 mAh external battery pack (approximately 3-4 phone charges) is the minimum companion for overnight use.
  - Paper topographic map and baseplate compass: zero battery requirement, works in any temperature, survives full submersion, complete situational awareness. Requires skill to use accurately (triangulation, bearing calculations, pace count). Should be carried on all trips beyond established, heavily signed trails.
  - Personal Locator Beacon (PLB): satellite-transmitted emergency signal (406 MHz), activates rescue response globally with no subscription. Not a navigation tool -- an emergency communication tool. Required consideration for anyone going into remote terrain without cell service.

- **Navigation redundancy rule by trip type:**
  - Established day hiking trail (marked, popular): phone with offline maps is sufficient primary
  - Remote day hiking or any off-trail: phone + paper map and compass
  - Any overnight backpacking: dedicated GPS or phone + external battery + paper map and compass
  - Remote overnight or multi-day: all of the above + PLB

---

### Step 7: Address Accessories That Are Safety-Critical (Not Optional)

This step is commonly omitted in generic gear guides but represents real safety and comfort gaps.

- **Hiking socks:** Material is wool (merino preferred, 60-85% wool blend with nylon for durability) or wool-synthetic blend. Avoid 100% cotton socks -- blister risk is substantially higher. Crew height covers ankle and lower boot top, preventing debris entry and friction from boot collar. Carry one extra pair on any trip over 6 miles or 4 hours.
- **Headlamp:** Lumen output 200+ lumens for trail use, red-light mode preserves night vision for camp use. Battery life at high output should be 2+ hours minimum. Lithium batteries in cold weather (below 32°F) are essential -- alkaline batteries lose 50-70% capacity at 0°F.
- **First aid kit (customized, not just purchased):** A pre-assembled kit should be supplemented with: moleskin and blister treatment (most important), an emergency space blanket (adds 2 oz, buys time in hypothermia), ibuprofen (anti-inflammatory for knee and foot pain common in new hikers), and the user's personal medications. Trim unnecessary items from pre-packaged kits to reduce weight.
- **Trekking poles:** Reduce knee load by 20-30% measured through force plate studies on descents. Adjustable length: set to 90-degree elbow angle on flat terrain, shorten by 5-10cm for ascent, lengthen by 5-10cm for descent. Carbide tips for rocky terrain, rubber tips for trail protection compliance in some wilderness areas.
- **Hydration:** 0.5 liters per hour of moderate activity in moderate temperatures, up to 1 liter per hour in heat or at elevation. 2-3 liter carrying capacity minimum for any day hike over 3 hours. Water filter (hollow fiber membrane preferred for ease of use) or purification tablets as backup for any water source beyond the trailhead.

---

### Step 8: Compile the Gear Profile and Purchase Prioritization

After working through all categories, synthesize findings into a structured output with specific recommendations, specifications, and a purchase priority order that reflects safety-critical items first.

- Footwear with specified construction, waterproof decision, fit protocol, and expected mileage
- Layering system with materials, weights, and climate-specific configuration
- Pack with volume range, frame type, torso length guidance, and fit test checklist
- Shelter specifications (if overnight) with HH ratings, weight budget, and season rating
- Navigation tool stack with primary, backup, and emergency communication
- Accessories (socks, headlamp, first aid, hydration) as named items, not a vague "miscellaneous" category
- Budget table with realistic current market pricing by tier

---

## Output Format

```
## Outdoor Gear Selection Guide

### Gear Profile
| Parameter          | Value                                                  |
|--------------------|--------------------------------------------------------|
| Primary activity   | [Day hike / Overnight / Multi-day / Car camping]       |
| Region and climate | [Specific geographic description and temp/precip range]|
| Use frequency      | [Occasional / Regular / Frequent with trip count]      |
| Budget tier        | [Budget / Mid-range / Premium + total budget target]   |
| Special constraints| [Growing child / wet climate / desert / beginner / etc.]|

---

### Footwear Recommendation
| Criterion              | Specification                                         |
|------------------------|-------------------------------------------------------|
| Category               | [Trail runner / Low-cut shoe / Mid-cut boot / High-cut boot] |
| Upper construction     | [Synthetic / Split-grain leather / Full-grain leather] |
| Waterproof membrane    | [Yes (ePTFE) / No -- reason based on climate]         |
| Lug depth target       | [3-4mm / 5-6mm / 7-9mm based on terrain]              |
| Midsole stiffness      | [Flexible / Moderate / Firm -- activity match]        |
| Expected mileage       | [300-500 / 500-800 / 800-1500 miles by construction]  |
| Fit test checklist     | Afternoon fitting / Hiking socks / Heel clearance 10-12mm / Downhill toe clearance / Heel lift under 7mm / 10 min walk test |
| Priority tier          | [Budget: $X-X / Mid-range: $X-X / Premium: $X-X]      |

---

### Layering System
| Layer  | Material Choice     | Weight Class      | Key Specification          | Climate Logic                    |
|--------|---------------------|-------------------|-----------------------------|----------------------------------|
| Base   | [Merino/Synthetic]  | [Light/Mid/Heavy] | [g/m² range]                | [Odor, drying time, temp range]  |
| Mid    | [Fleece/Down/Synth] | [100/200/300-wt]  | [Fill power or g/m²]        | [Wet/dry condition logic]        |
| Outer  | [Hard/Softshell]    | --                | [HH rating / MVTR g/m²/day] | [Precipitation probability]      |
| Camp   | [Down/Synth puffy]  | --                | [CLO estimate]              | [Rest-only -- do not hike in]    |

**Active configuration for this profile:** [Base + X / Base + Mid + Shell / etc.]
**Emergency pack configuration:** [List layers to carry but not wear]

---

### Pack Specification
| Criterion          | Specification                                          |
|--------------------|--------------------------------------------------------|
| Volume range       | [X-X liters]                                           |
| Frame type         | [Frameless / Flexible stay / Rigid internal]           |
| Torso length       | [Measure C7 to iliac crest -- target size range]       |
| Hip belt position  | [On iliac crest, buckle at navel line]                 |
| Key features       | [Hip belt / Load lifters / Compression straps / Rain cover / Side pockets] |
| Load test          | Load with [X lbs], walk 10-15 minutes, verify hip belt position |
| Priority tier      | [Budget: $X-X / Mid-range: $X-X / Premium: $X-X]      |

---

### Shelter Specification (Overnight and Multi-Day Only)
| Criterion          | Specification                                          |
|--------------------|--------------------------------------------------------|
| Tent type          | [Freestanding / Semi-freestanding / Tarp]              |
| Season rating      | [3-season / 3+season / 4-season]                       |
| Fly HH rating      | [Minimum Xmm HH]                                       |
| Floor HH rating    | [Minimum Xmm HH]                                       |
| Rated capacity     | [X-person for Y actual sleepers]                       |
| Weight target      | [Under X lbs per person]                               |
| Sleeping bag rating| [Comfort to X°F / Lower limit to X°F -- EN rated]     |
| Sleeping pad R-value| [Minimum R-X for expected ground temps]               |
| Priority tier      | [Budget: $X-X / Mid-range: $X-X / Premium: $X-X]      |

---

### Navigation Stack
| Tool                   | Role          | Specification                         | Notes                            |
|------------------------|---------------|----------------------------------------|----------------------------------|
| [Primary tool]         | Primary       | [Battery life / accuracy / features]  | [Download maps before departure] |
| [Secondary tool]       | Backup        | [Paper map scale and datum]            | [Compass + declination note]     |
| [Emergency device]     | Emergency     | [PLB if remote / battery pack size]    | [When to carry]                  |

**Magnetic declination for this region:** [X degrees E/W -- apply when using compass]

---

### Safety Accessories
| Item             | Specification                              | Notes                                 |
|------------------|--------------------------------------------|---------------------------------------|
| Hiking socks     | [Merino wool blend, crew height]           | Carry 1 spare pair on trips 6+ miles  |
| Headlamp         | [200+ lm, red mode, lithium batteries]     | Always carry even for day hikes       |
| First aid kit    | [Base kit + moleskin, space blanket, ibuprofen] | Customize, don't just buy pre-packed |
| Hydration        | [X liters capacity, filter type]           | 0.5-1L/hr depending on conditions    |
| Trekking poles   | [Adjustable, carbide tips -- if applicable]| 20-30% knee load reduction on descents|

---

### Budget Summary
| Category         | Budget Tier     | Mid-Range Tier   | Premium Tier     | This Profile    |
|------------------|-----------------|------------------|------------------|-----------------|
| Footwear         | $60-100         | $120-180         | $180-350         | $[X-X]          |
| Base layer       | $25-40          | $50-85           | $90-150          | $[X-X]          |
| Mid layer        | $30-60          | $70-130          | $140-250         | $[X-X]          |
| Outer shell      | $50-90          | $100-180         | $200-400         | $[X-X]          |
| Pack             | $40-80          | $90-180          | $200-400         | $[X-X]          |
| Shelter (tent)   | $60-120         | $150-350         | $400-800+        | $[X-X]          |
| Sleep system     | $50-120         | $150-350         | $400-700+        | $[X-X]          |
| Navigation       | $0-30           | $30-80           | $150-400         | $[X-X]          |
| Accessories      | $30-60          | $60-120          | $100-200         | $[X-X]          |
| **Total range**  | **$X-X**        | **$X-X**         | **$X-X**         | **$[X-X]**      |

---

### Purchase Priority Order
1. **[Category]** -- [Specific reason this is highest priority: safety, prevents injury, etc.]
2. **[Category]** -- [Specific reason]
3. **[Category]** -- [Specific reason]
4. **[Category]** -- [Specific reason; can substitute with existing gear temporarily]
5. **[Category]** -- [Lower urgency; upgrade from budget as budget allows]

### Interim Substitutions (if budget is being spread across multiple purchases)
- [Category]: [What the user can use in the meantime and its limitations]
- [Category]: [What the user can use in the meantime and its limitations]
```

---

## Rules

1. **NEVER recommend specific brands or product names.** Provide measurable specifications (fill power, HH rating, R-value, lug depth, g/m²) so the user can evaluate any product against objective criteria. This is more useful than brand loyalty and keeps recommendations timeless.

2. **ALWAYS complete the fit testing protocol for footwear and packs.** Footwear that does not fit correctly is the leading cause of hiking-related blisters, black toenails, ankle instability, and knee stress. A pack with wrong torso length or improperly positioned hip belt causes back pain, shoulder nerve compression, and dangerous imbalance. These are not style preferences -- they are biomechanical requirements.

3. **NEVER recommend cotton as a base layer, mid layer, or sock material for active outdoor use.** Cotton holds moisture against the skin, dries slowly, and provides negative insulation when wet. This is a documented contributor to hypothermia at temperatures well above freezing (50°F with wind and rain is sufficient). Treat this as a non-negotiable rule, not a preference.

4. **Always specify sleeping bag ratings using EN/ISO comfort temperature, not the manufacturer's "rated to" temperature.** The EN comfort rating (designed for a female sleeper) or lower limit (designed for a male sleeper) represents actual comfortable sleeping temperature. The "rated to" temperature on non-standardized bags is often the survival extreme, which is 15-25°F colder than the comfort range.

5. **Navigation recommendations must always include a non-powered backup.** Phone batteries die, GPS devices fail in cold, and electronic screens crack. A paper topographic map and baseplate compass work at any temperature and require no charging. Every overnight recommendation must include this backup. Specify the correct magnetic declination for the region.

6. **Budget tier prices must reflect current realistic market ranges.** Footwear at the budget tier starts at $60-80 for functional trail runners, not $20 sneakers. Mid-range hardshell jackets are $100-180, not $50. Sleeping bags rated to comfort at 20°F start around $80 at budget tier and $200+ at premium. Use current market reality, not aspirational or outdated pricing.

7. **Weight targets must be specified per activity type, not as universal targets.** Ultralight backpacking targets (base weight under 10 lbs, shelter under 2 lbs per person) are not appropriate for car campers and are difficult for beginners. Car camping has no meaningful weight constraint. Day hiking gear should total under 20-25% of body weight in pack load. Overnight backpacking pack loads above 30-35% of body weight measurably increase injury risk.

8. **Shelter recommendations for overnight backpacking must always include sleeping pad R-value guidance, not just sleeping bag temperature rating.** Cold ground conducts heat away from the body faster than cold air. A hiker in a 20°F sleeping bag on a R-1 foam pad will be cold at 40°F ambient because ground temperature is lower and the pad provides insufficient insulation. These two specifications work together as a system.

9. **Durability and investment advice must scale explicitly with use frequency.** An occasional hiker (under 25 trips/year) buying premium full-grain leather boots may not break them in properly before they deteriorate. A frequent hiker (50+ trips/year) buying budget synthetic footwear will replace them every 6-9 months at greater lifetime cost than a single premium purchase. Make this math explicit in the recommendation.

10. **Always include interim substitution advice when the user has a limited total budget.** A user who cannot afford to buy the full kit at once needs to know what existing gear (athletic clothing, school backpack, cotton socks replaced with borrowed merino) can bridge the gap safely until proper gear is purchased. This prevents the user from skipping a safety-critical item because they cannot afford everything simultaneously.

11. **Down insulation must always be flagged as a wet-weather risk.** When conditions include precipitation probability above 30% or sustained high humidity, explicitly note that down loses 80-90% of insulating value when wet and synthetic insulation should be specified instead. This is especially critical for mid layers and sleeping bags -- a wet down sleeping bag in a cold environment is a life-safety issue.

---

## Edge Cases

### Very tight total budget (under $200 for a complete kit)

Prioritize in strict safety order: footwear first, shelter second (if overnight), outer shell third. Trail runners in a synthetic build can be found for $60-80 new or $25-40 at secondhand sporting goods stores, and they are functional for day hikes under 10 miles. A rain jacket from a general retail store at $30-50 is acceptable for occasional use -- it will not have 10,000mm HH but will provide meaningful rain protection for short durations. Do not recommend a dedicated outdoor pack at this budget -- a school-style daypack with hip belt, if available, is acceptable for loads under 15 lbs and distances under 8 miles. Merino wool base layers can sometimes be found at thrift stores; synthetic athletic tops (polyester, not cotton blend) from general retailers cost $15-25 and are acceptable substitutes. Army surplus stores sell wool blankets, leather boots (variable quality), and ponchos at low cost -- inspect footwear for sole delamination and leather for cracking before recommending. Flag clearly that cotton socks are unacceptable even at this budget tier; wool hiking socks are $12-18/pair and represent a mandatory spend.

### User in a consistent hot, dry desert climate (Sonoran, Mojave, Colorado Plateau)

Invert the standard priority hierarchy. Thermal insulation management becomes secondary to sun protection and hydration capacity. Base layer should be lightweight (100-130 g/m²), light-colored (reflects radiant heat), and UPF 40+ rated -- UPF 50 blocks 98% of UV-B. A full-brim sun hat (minimum 3-inch brim, preferably 360-degree coverage) is more important than any insulation layer for summer desert hiking. Hydration planning becomes the primary constraint: minimum 1 liter per hour in summer desert conditions above 90°F, with no reliable water sources beyond the trailhead. Pack volume must accommodate 4-6 liters of water carrying capacity in extreme conditions. Waterproof membranes in footwear are counterproductive in dry desert heat -- they reduce breathability and increase internal temperature without providing meaningful benefit (desert soils shed the rare rain quickly). Recommend breathable synthetic mesh footwear. However, flag that dramatic temperature drops (40-50°F swings between day and night) occur in desert environments -- a lightweight puffy and wind layer are still required for overnight trips. Flash flood awareness: avoid slot canyons during monsoon season (July-September in the US Southwest) regardless of local weather conditions.

### User in a consistently cold, wet climate (Pacific Northwest, coastal Scotland, Southeast Alaska, Appalachian shoulder season)

Waterproofing and wet-performance insulation become the overriding criteria across all categories. Down insulation should not appear in any layer recommendation that will be exposed to rain -- recommend synthetic fill for mid layers and sleeping bags. Hardshell outer layer is mandatory (softshell is insufficient); minimum 20,000mm HH with fully taped seams and hood. Footwear with waterproof membrane is essential; recommend full-grain leather or leather/synthetic mix with ePTFE membrane. Pack should have an integrated rain cover or be lined with a waterproof trash compactor bag (8-mil contractor bag, $0.50-1.00, works better than most pack covers). Sleeping bag: 100% synthetic fill rated with EN comfort standard for expected overnight lows. Sleeping pad should be R-3 minimum even in summer to account for ground moisture. Cotton avoidance is especially critical -- wet cotton accelerates hypothermia onset and is the most common contributing factor in Pacific Northwest hypothermia incidents. Carry full dry bag storage for insulation layers and sleeping bag within the pack.

### User transitioning from car camping to overnight backpacking

This transition requires the most targeted gear replacement advice. The weight that is inconsequential in a car is back-breaking on a trail. Prioritize replacement in this order:

1. Sleeping bag: car camping bags are often 5-8 lbs and rated to 0°F (far more than needed), versus a 3-season backpacking bag at 2-3 lbs. This is the single biggest weight savings available.
2. Sleeping pad: foam car-camping pads can be replaced with a self-inflating or inflatable backpacking pad for a 1-2 lb savings.
3. Shelter: car camping family tents are 8-20 lbs. A 2-person backpacking tent is 3-5 lbs. Replace in the first or second purchasing cycle.
4. Pack: car camping duffels and coolers are not trail-compatible. A 50-55 liter internal frame pack with hip belt is the transition vehicle that makes everything else manageable.
5. Cook system: large car camping stoves and full cooksets are too heavy. Transition to a canister-top stove (100-150g) and a 0.9-1 liter titanium or hard-anodized aluminum pot.
Frame the transition as a 2-3 purchasing cycle project, not a single purchase. Do not recommend replacing everything simultaneously -- it creates sticker shock and causes buyers to over-compromise on quality.

### User buying gear for a child or fast-growing teenager

Investment in premium footwear for a growing child (under 16) is wasteful -- foot size typically changes every 6-12 months for pre-teens and every 1-2 years for teenagers. Recommend mid-range or budget footwear with appropriate material (not cotton socks, not flat sneakers on rocky trails). Do not attempt to buy extra size in trail footwear to compensate for growth -- the heel-clearance and toe-clearance fit specifications are safety requirements, not style preferences. Extra-large footwear causes heel blisters, ankle instability, and toe strike injuries. A half-size or one size of room is acceptable; two or more sizes over is not. Focus premium investment on the outer shell (hardshell rain jacket can be bought with room to grow -- one size up with cinchable hem and cuffs is acceptable), which lasts multiple growth cycles. A day pack for a child under 12: maximum loaded weight should not exceed 10-15% of the child's body weight (versus 20-25% for adults). Fit the torso length carefully -- youth-specific packs cover the S-XS torso range (10-15 inches) and have appropriately narrowed shoulder straps.

### User asking about gear for high altitude (above 10,000 feet / 3,000 meters)

Standard 3-season layering rules are insufficient above 10,000 feet where temperature drops 3-5°F per 1,000 feet of elevation gain, UV index is 25-50% higher per 1,000 feet than at sea level, and weather changes occur significantly faster. Specific additions beyond standard recommendations: all three layers should be carried even on a "summer" day hike because summit temperatures can be 15-25°F below trailhead temperatures. Sun protection (SPF 50+ sunscreen applied every 2 hours, UV-protective sunglasses rated UV400 or higher) is critical -- snow reflection above treeline creates full-body UV exposure from above and below simultaneously. Hydration requirements increase at altitude because dry air and increased respiration rate raise water vapor loss. Acclimatization is the most critical safety factor above 8,000-10,000 feet -- recommend sleeping at altitude 1-3 nights before attempting strenuous day hiking. This skill does not cover the technical gear required for alpine climbing (crampons, ice axe, rope systems) -- flag clearly and redirect if technical climbing terrain is involved.

### User with a pre-existing injury or chronic condition affecting gear selection

This is a common scenario that generic gear guides ignore. The most frequent presentations:
- **Chronic knee pain or prior knee surgery:** Trekking poles are close to mandatory, not optional -- specify proper length and anti-shock feature if available. Footwear should prioritize cushioned midsole (not minimalist). Avoid downhill-heavy routes in early trips. Pack weight should stay well below 20% of body weight initially.
- **Plantar fasciitis:** Recommend footwear with structured arch support and cushioned heel cup. Avoid zero-drop or minimal-stack footwear. Replace footwear at the lower end of the mileage range -- midsole compression is the primary issue.
- **Wide feet or bunions:** Fit testing becomes even more critical. Request a wide-width (EE or 2E for men, D or EE for women) sizing option. Never force a narrow-last boot onto a wide foot -- the compression causes metatarsal stress fractures over time.
- **Back problems:** Pack fit and hip belt load transfer are critical. A poor-fitting pack with 25 lbs transfers load to the lumbar spine rather than hips. Trekking poles reduce trunk rotational load during walking.
Do not provide medical advice. Recommend consulting a sports medicine physician or certified pedorthist for footwear fitting if the condition is severe. Focus guidance on gear selection criteria that reduce mechanical stress.

---

## Example

**Input:** "I just moved to Colorado and want to get into day hiking and maybe try an overnight camping trip later this year. I'll probably go once or twice a month in spring and fall. I'm completely new to this -- I don't own any dedicated hiking gear. I'm female, 5'6", and I'd describe my budget as mid-range. I'm not sure what that means for outdoor stuff but I don't want the absolute cheapest, and I don't have thousands to spend."

**Output:**

## Outdoor Gear Selection Guide

### Gear Profile
| Parameter          | Value                                                         |
|--------------------|---------------------------------------------------------------|
| Primary activity   | Day hiking (initially), overnight backpacking (later season)  |
| Region and climate | Colorado Front Range and mountains -- elevation typically 6,000-14,000 ft depending on trail; daytime temps 40-75°F spring/fall; afternoon thunderstorms frequent May-September; UV index very high above 10,000 ft; possible snow on high trails through June and starting September |
| Use frequency      | Regular (
