- Good fit are important.
- A fixed suspension is lighter weight; adjustable suspension can provide more comfort.
Backpacks are categorized by trip length, based on the pack's capacity and suspension system. The larger backpacks are for extended trips, while smaller packs are shorter ones.
Custom Fit Packs
- Extended: They provide substantial suspension and load support, suitable for long backpacking trips of a week or more or for cooler seasons when you need to carry lots of clothing.
- Men's packs hold more than 80 liters (4,881 cu. in.) of gear capacity.
- Women's packs hold more than 70 liters (4,300 cu. in.) of gear capacity.
- Multiday: Backpacks with 50-75 liters (3,051-4,576 cu. in.) of gear capacity. Comfortable for medium to heavy loads; a good choice for 2- to 4-day trips.
- Weekend: Backpacks with a gear capacity of 40-50 liters (2,440-3,051 cu. in.) for men's packs and 35-45 liters (2,135-2,745 cu. in.) for women's packs. These packs are designed for 1- to 3-day trips, perfect for short jaunts and ultra-light roams.
- Daypacks: Designed primarily for day use on trail hikes.
- Hydration Packs: provides hands-free drinking while hiking or biking. Generally includes a reservoir, usually 2 (70 fl. oz.) - 3 (100 fl. oz.) liters in size.
- Custom molding/sizing: Some backpacks can be molded, sized and shaped for a better fit of a body’s contours. This can provide a better fit, increase comfort and reduce break-in time. Torso length measurements are a critical element of a good pack fit.
- Adjustable suspension: Allows for fine-tuning a pack's torso fit.
- Fixed-suspension: Less complex and lighter than comparable adjustable models.
- Women-specific packs: The shoulder straps and hip belts have been modified specifically for women’s torso lengths.
Backpacks can be divided into three general classifications, depending on pack's weight, comfort and safety.
- Deluxe: Where comfort and convenience features are the priority.
- Lightweight: Offers a balance between low-weight innovations and useful features.
- Ultra-light: Fore-goes conveniences to reduce pack weight.
- Hip belts: Comfort and adjustability are important for larger packs. More sophisticated hip belts allow for rotation and flex, while others offer dynamic ones adjust range of movement.
- Hydration compatibility: Most packs have a sleeve for a fluid reservoir and a port for its sip tube.
- Rain covers: Some packs include a rain cover that protects your gear from the rain.
- Support-frame materials:
- Some packs use Aluminum (and other lightweight metal) stays to transfer the weight of the pack to the hip belt.
- Some packs use a stiff plastic (HDPE) frame sheet for support. It also shields backs from protruding items.
- Other packs offer a stay/frame sheet combo.
- Suspended mesh back panel: Some frame designs use taut, suspended mesh to create an air space behind your back. The result: increased comfort and airflow that cools your back. Other packs feature molded foam channels or raised foam patterns designed to provide a similar cooling effect.
- Top (lid) storage: offers extended capacity, as do expansion collars. Some lids double as waist packs for day trips from basecamp. They also offer the best weather protection.
- Top- or panel-loading: Almost all packs feature access to the main compartment at the top of the pack or via a front panel. Top-load design minimizes weight, while panel-load design offers easy access to your gear. Top-load design is also the best waterproof design for packs.