How to Choose a Daypack

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The below article is forwarded from http://www.rei.com/expertadvice/articles/daypack.html

How to Choose a Daypack

For any activity that involves more gear than you can carry in your pockets — hiking, climbing, a full day at school — you can find a daypack that will make the experience more efficient and better organized.

Panel Loader or Top Loader?

Panel-loading daypacks offer a main storage compartment that is accessed via a U-shaped zipper. Fully opened, one sidewall (or panel) of the compartment falls away like a flap.

Such a wide opening makes panel loaders easier to load and rummage through when you're searching for something. This makes them particularly appealing for students, parents or trip leaders. If organization is important to you, consider a panel loader.

Top-loading daypacks generally are simpler in design and a little lighter than panel loaders of a comparable size. (Zippers and extra compartments add ounces.) Top loaders, which usually close with a drawstring, are also easier to overstuff when needed.

Some top-loaders offer a "floating" (extendable) top lid that creates space for extra gear so you can exceed the pack's stated capacity. This is valuable to climbers who may need to carry a lot of gear during the approach but don't want to climb with a larger volume pack once most of the contents (rope, rack, shoes, helmet) are in use.

Top loaders with side compression straps also do a nice job of stabilizing a load, making them appealing to climbers, scramblers and skiers.

The downside? Organizing and locating gear in a top loader can be a challenge. Something important, it seems, always migrates to the bottom of the pack.

A few daypacks offer dual access points—top and panel. That's a handy option.

What's the Best Size?

The sweet spot for most hiking and multisport daypacks is 30 liters (roughly 1,800 cubic inches). That's enough capacity to hold the 10 Essentials plus some extras.

Some specialized packs lie at the far ends of the daypack-capacity continuum. A trail-running pack may be designed to hold as little as 10 liters (600 cu. in.). A climbing pack may hold 40 to 50 liters (around 2,400 to 3,000 cu. in.).

Are you often a trip leader? Someone who carries extra gear for other members of your family such as small children? Look for a pack in the 40-liter range—perhaps even larger.

In most cases, though, packs with capacities at or near 30 liters are a popular choice for a typical day hike.

Match Your Pack with Your Activity

If you day hike in the summer and ski tour in the winter, you may want more than one daypack to accommodate both activities. If, however, you'd prefer a single, do-it-all pack, evaluate your ambitions and expectations.

For example, will your pack get as much use (or more?) at school as it will on the trail? Then steer yourself toward a larger-capacity book bag. Plan to do some scrambling during some of your hikes? Consider packs with narrower profiles so your arms have room to swing freely.

Day hiking: The following attributes or features are often preferred by day hikers:

    * an adequate capacity, typically 30 liters
    * side pockets (usually elasticized mesh slots that lie flat against the pack until you wedge an item into place)
    * compartments (slots or pockets) for organizing small items and loose gear
    * hydration-system compatibility

Scrambling/climbing: Choose a narrow-profile pack, perhaps one that includes a padded back or a framesheet. Often you'll be climbing to higher elevations where the air is cooler, so you'll need a capacity of 40 liters (about 2,400 cubic inches) or so to hold extra clothing.

Your ambitions will determine whether you need a lower-capacity multiday backpack or a large technical daypack. Compare your standard equipment load (ropes, carabiners, etc.) with the list of specialized features a pack may provide (ice axe loop, crampon patches, daisy chain).

A variety of load-stabilizing compression straps and a sternum strap are also valuable. Ask your climbing companions what features work best for them.

Ski touring: A smooth, narrow profile is a plus. Your range of travel (and the extra clothing you usually carry) will determine your capacity requirements. Look for a means to attach your skis to the pack and a secure place to keep your shovel and probe handy. A sternum strap and hipbelt are essential. Climbing packs often work very well for backcountry touring.

Trail running/adventure racing: A lumbar pack, water-bottle pack or small technical daypack (at 25 liters or less) are all good choices. Lumbar packs (also called waist packs) are less inclined to shift while you run, and it's nice to keep your back clear so perspiration can escape.

Overnighters: If you have a minimalist's mentality and the gear to match it (a teeny sleeping bag; a bivy sack or similar next-to-nothing shelter; and so on), a technical daypack can handle an ultralight overnight load. Typically, packing with such efficiency is a talent of an elite few. Newcomers to the ultralight scene are probably better advised to go with an ultralight multiday pack.

You may want to look for a pack that offers a padded back (or some type of framesheet) to help support a load, a modest lumbar pad and a padded (though not necessarily beefy) hipbelt. Some models offer one or two aluminum stays to accommodate a heavier load. The more amenities you crave, of course -- even during an overnight trip -- may push you into a larger multiday pack.

School/Commuting/Traveling: Look for packs that offer at least one divider, 2 or more compartments, a slot for stashing magazines or notebooks, space for your electronics and an organizer panel (to hold your pens and other small, loose items). A padded back panel will prevent corners of books from gouging your back.

Specialized Packs

Women-specific: The chief advantage here is improved fit, accomplished through contoured shoulder straps and, on some packs, a narrower design.

Hydration: Most daypacks sold at REI are compatible with common hydration reservoir systems ranging from 1 to 3 liters. (Often the reservoir with sip tube are sold separately.) Packs labeled "hydration packs" come equipped with reservoirs and hose systems and thus likely cost more than "hydration-compatible" packs.

Lumbar: These are waist packs that ride on the small of your back as well as your waist. Their snug, stable design is very popular with trail runners.

Sling bags/courier-style bags: Designed to be worn over one shoulder, these are popular among cyclists. People like their distinctive looks.

Day bags: A smaller, more fashion-conscious variation of the traditional daypack. Fashionable yes, and functional, too.

Ventilated Back Panels

This relatively recent design feature uses lightweight framing (or other engineering techniques) to suspend the load away from your back. The result: A steady flow of air can reach your back. This delivers a big bonus in comfort when carrying a pack on warm days. Packs from Gregory, Osprey and Deuter are among the first packs to offer this innovation.

Note: If you routinely carry bulky or heavy loads, these packs may not be your best choice—a heavy load suspended away from your body could affect your balance. If you are shopping for such a pack at an REI store, try loading it with some weight and take a test-stroll around the store to gauge how it carries.

Fabrics and Coatings

Nylon does an excellent job of withstanding abrasion and tearing and is the fabric most frequently used in pack construction. Nylon twill, which features a sturdy diagonal weave, is commonly found in packs.

Ripstop fabrics (nylon, polyester and nylon/polyester blends) are woven in a manner that creates box- or diamond-shaped patterns, creating a reinforced grid. Such "ripstop" fabric inhibits a tear from expanding beyond its point of origin.

Kodra fabrics (usually nylon) use high-tenacity fibers to enhance resistance to abrasion and tears. Their downside: The burly fibers tend to be heavy. Kodra is a generic name for such fabrics. The brand-name variation is Cordura®.

Nylon oxford is a light, smooth fabric (characterized by a plain weave) that has been used in pack construction for decades.

Nylon/polyester blends are principally used to provide different colors within one fabric. It's a fashion thing.

Hypalon® is flexible synthetic rubber used to reinforce areas of high abrasion, often the edges or key touch points of packs. It is sometimes used to create patches. It is used sparingly on packs due to its weight.

The denier (a unit of fineness for yarn) of a fabric used in packs influences its abrasion resistance and, subsequently, its weight. Packs made for the minimalist or ultralight explorer may use fabrics as light as 70 denier. Rough, tough ballistic nylon, meanwhile, is often rated 1,680 denier. Higher abrasion resistance comes with a higher denier fabric, which includes a corresponding higher weight.

Polyurethane (PU) is the standard coating applied to the interior walls of packs. It provides significant water resistance (though not waterproofness — so if you dunk your pack in a lake, its contents will eventually get wet).

A silicone coating (or impregnation) is used on lightweight, low-denier fabrics to minimize weight. It provides very high tear strength, though silicone can break down faster than a PU coating. PU coatings may also provide better water resistance. Some manufacturers boast that holes in silicone-treated nylon can be "healed" by rubbing the hole with your fingers. This is possible if the tear-resistant fibers have been pushed apart, not torn.

What Makes a Quality Daypack?

Many stores sell backpacks. So which is a better value: A bargain pack from a department store or a well-engineered technical pack? You may wonder: "A daypack is a daypack, right? It's a sack attached to a couple of shoulder straps. How different can they be?"

You'll initially save money with a bargain pack, but you'll likely miss out on design refinements found in top-brand packs that deliver better performance, convenience and comfort. Such as? Well, to name a few:

    * Padding, support and shaping: Shoulder straps and, on some models, scapula pads, offer plusher padding and great longevity in comfort; some packs include shaped bottoms or structured back panels to prevent loads from sagging, keeping items closer to your back.
    * Women-specific designs: Shoulder straps are contoured to comfortably conform to the female form; some offer narrower profiles.
    * Tougher fabrics at lighter weights: Discount packs commonly use weightier fabrics purchased in bulk to cut costs; more sophisticated packs may use a rugged 630-denier nylon that offers superb durability at a noticeable weight savings.
    * Ventilated back panels: Mentioned previously.
    * Sustainable fabrics and materials: An emerging trend already seen in packs such as the Osprey React.
    * Water-resistant zippers: Eliminates storm flaps, saving weight and creating a cleaner look. Many times these zippers are welded, or glued, in place. This eliminates stitching, increases watertightness, boosts strength and further reduces weight.
    * Waistbelt pockets: Handy for keeping small items (gel packs, for instance) within easy but unobtrusive reach.
    * Hydration system compatibility: Some packs include sleeves for a hydration reservoir; most offer a port for a hydration hose.
    * Tool loops and daisy chains: External attachment points for an ice axe, crampons, climbing gear, trekking poles.
    * Small but useful nuances, including:
          o Padded back panels
          o Media pockets, even earbud holders
          o Laptop slots or sleeves in school, commuter or travel packs
          o Organizers and keyholders