Hyperlite Mountain Gear Southwest 3400 Pack

The Southwest 3400 is their workhorse 55-liter backpacking pack, weighing approximately 2 pounds and constructed almost entirely from white Dyneema laminate that is inherently waterproof without requiring a rain cover or pack liner. The seams are sealed with waterproof tape, and the roll-top closure eliminates the zipper failure points that plague conventional packs.

Dyneema does not absorb water, does not stretch, does not rot, and resists abrasion and puncture at a level that makes hikers who have used it for years struggle to find wear. The pack uses an aluminum stay frame with a removable hipbelt and load lifters, carrying 35 pounds comfortably for thru-hikers who have dialed in their base weight.

Hyperlite offers a lifetime warranty against manufacturing defects and performs repairs in their Maine facility. At roughly $340, the Southwest 3400 costs more than most ultralight frameless packs, but the Dyneema construction and lifetime warranty transform the math: thru-hikers on r/ultralight report multiple long trails on a single pack with no signs of degradation.

The white color shows dirt readily, which is cosmetic rather than functional. For weight-conscious backpackers who need a pack built from the strongest fabric available, Hyperlite is the American manufacturer that turned sailcloth into a backpacking revolution.