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This product is no longer available, but don't go just yet.


  • Narrow back and shoulder profile, canted hipbelt and short frame are designed to comfortably fit a woman's body
  • Patent-pending ergoACTIV hipbelt, breathable back panel and soft, 3D mesh lining on hipbelt and shoulder straps provide topnotch support and comfort
  • SwingArm™ shoulder straps move in concert with a hiker�s stride or a climber�s reach by sliding through the bottom of the pack with a low-friction cable and housing
  • Shoulder straps are linked to the other by the cable which helps maintain an even, balanced load across the shoulders
  • An ideal blend of volume, comfort and mobility lets you bring everything you need without slowing you down or limiting your range of motion
  • Top-loading pack body features a floating lid to accommodate large or small loads; giant U-shape front-panel zipper offers easy access
  • Hydration compatibility lets you add a reservoir of your choice (reservoir sold separately)
  • Hipbelt stash pocket, side stretch pockets and zippered front pocket offer plenty of storage for water bottles, snacks and other essentials
  • The Black Diamond Onyx 55 pack features retractable tool loops that allow ice axes or trekking poles to be lashed to the outside of the pack


View all Black Diamond Backpacking Packs

REI membership


Best Use Backpacking
Frame Type Internal
Gear Capacity (L) 55 / 57 liter
Gear Capacity (cu. in.) 3,356 / 3,478 cubic inches
Weight 4 lbs. 9 oz. / 4 lbs. 10 oz.
Weight - Metric 2.10 / 2.11 kilograms
Fits Torso 15.5 - 18.5 / 17.5 - 20.5 inches
Fits Waist/Hips 30 - 35 / 34 - 39 inches
Material(s) Polyester/nylon
Frame Material HDPE framesheet/6061-series aluminum
Number of Stays 6mm peripheral hoop/20mm center stay
Suspended Mesh Back Panel No
Pack Access Top / front
Number of Exterior Pockets 5 + main compartment
Sleeping Bag Compartment Yes
Gender Women's
Backpack Style Lightweight

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REI's guarantee doesn't cover ordinary wear and tear or damage caused by improper use or accidents.

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