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Sierra Designs Flex Lumbar 3-6 waist pack, black, front view, contracted

Takes Weight Off Your Back and Onto Your Backside

The Flex Lumbar collection takes the same expanding gusset found in our Flex Capacitor, and shifts it vertically to work as a lumbar pack. Integrated water bottle pockets and enough room to stash a layer and some food means you have your bases covered for any day hike. Flex it open when you need to carry more, or cinch it down when you want a lower profile pack.


  • Stretch mesh water bottle pockets
  • Zippered valuables pocket
  • 1 main compartment, 1 hidden top zipper
  • Vertically expandable volume
  • Dual compression straps to stabilize load
  • Padded hip belt for on-trail comfort


  • 100D Nylon-Poly Ripstop

Tech Specs

  • Capacity: 3-6 liters / 183-366 in3
  • Weight: 8 oz / .23 kg
  • Hip fit: 52" / 132 cm max
  • Dimensions (H x W x D): 6" x 10" x 5" / 15.2 x 25.4 x 12.7 cm
New Badge: Yes

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    Flex Lumbar 3-6

    Out Of Stock