Hyperlite Mountain Gear

Southwest 40L Backpack

What Our Gearhead® Experts Are Saying:

"I use the Southwest 40L when I want a pack that’s minimal but still bomber for rough trails. The Dyneema fabric shrugs off abrasion and keeps gear dry, and the solid side pockets are perfect for protecting water bottles and fuel canisters. It’s compact enough for weekends but has the durability to handle thru-hikes."

Built for tough terrain and long trails, the Hyperlite Mountain Gear Southwest 40L Backpack delivers the strength and simplicity we count on in ultralight form. Constructed with Dyneema Composite Fabric, it’s both waterproof and abrasion resistant, giving us confidence in desert canyons, alpine ridges, and thick brush. The roll-top closure and fully seam-sealed construction keep gear dry while trimming unnecessary weight.

The Southwest 40L thrives in variable conditions. Solid Hardline with Dyneema pockets resist punctures and shield essentials from rough trails, while the internal frame, padded hip belt, and contoured aluminum stays provide a stable, comfortable carry. Compression straps keep the load tight when we pack light, and hydration compatibility ensures we stay fueled on long pushes. Whether it’s a weekend fastpack or a section of the PCT, the Southwest 40L is a rugged partner for ultralight adventures.