Sierra Designs

Flex Capacitor 40-60L Backpack with Waist Belt | ** New 2023 Version **

Colour: Butterscotch

Versatile gear-hauler with unique expansion system

The Flex Capacitor really is like no other backpacking rucksack out there. This lightweight, versatile pack has an impressive 20 litres of adjustable volume, giving you the option of packing 40L or 60L, making it the perfect pack for anything from overnight camps to multi-day trips. And unlike most packs, a clever front gusset means it expands outwards, not upwards – keeping your load stable and secure rather than teetering and top-heavy, even at full capacity. The lightweight Y-flex suspension system means you’ll barely feel your load and there are plenty of clever pockets too. This includes a stash pocket in the lid, two roomy side pockets, two stretchy chest pockets on the shoulder straps and zippered hip belt pockets to keep your kit organised, whatever the adventure

    • Lightweight Y-Flex Suspension provides superior increased support
    • 20L of adjustable volume means you can use this pack for extended backpacking trips or shorter day trips
    • Hydration sleeve doubles as a removable summit sack by using the two cinch straps from the front of the backpack
    • Dual adjusting shoulder straps tailors pack fit to your torso
    • 2 hydration pockets on shoulder straps
    • 2 stretch mesh side pockets to keep essentials close at hand
    • Zippered hip belt pockets for easy storage
    • U-shaped top access zipper for easy access while backpacking
    • 100D Nylon Honeycomb/420D Oxford
  •   S/M Torso M/L Torso
    Capacity 40-60 L 40-60 L
    Weight 1.23 kg 1.4 kg
    Torso Fit 41 - 48 cm 46 - 53 cm
    Hip Fit with Belt 63 x 20 x 32 cm 70 x 22 x 32 cm
  • Sustainability Through Longevity - Sierra Designs products are covered by a Lifetime Warranty against material and workmanship defects

  • Maybe it’s no wonder that the state of California has been the cradle for so many great American outdoor brands. Sandwiched between the Pacific Ocean and the Sierra Nevada mountains, and encompassing no less than nine US National Parks, the Golden State has long been a mecca for outdoor adventurers of every ilk. Sierra Designs is a case in point. California was the natural place for the brand’s co-founders, a pair of young outdoor aficionados named George Marks and Bob Swanson, to set up shop.

    They first met in late 1963 at while working at The Ski Hut in Berkeley, CA. Two years later, Sierra Designs was born. Today, the brand continues to create outdoor equipment and apparel that is functional, beautiful, and most importantly, attainable, enabling outdoor lovers throughout the USA and beyond to hit the trail and fill their souls with a sense of wanderlust.

Great fit. Super efficient packing and unpacking. Very light.

-Andy H, Verified Buyer


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