Outdoor Research Alpine AscentShell Bivy

Color: Nimbus
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Members get an estimated $29.90 (10%) back on this item.
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Ideal for alpine pursuits and extreme weather, the Outdoor Research Alpine AscentShell bivy combines the cult-classic Alpine Bivy with Helium AscentShell tech for drastically improved breathability.


  • Helium AscentShell technology leads to less condensation and a more comfortable sleep
  • Compared to a clamshell opening, the large, step-in opening allows you to step out of your boots and straight into the bivy easily without any shimmying
  • Durable, waterproof and breathable fabric is fully seam-taped for protection from the elements
  • Fly fastener exposes the extra-large mesh screen for stargazing
  • No-see-um mesh helps keep the bugs out
  • High-volume toe end, plus extra head room to store your gear
  • Single-pole system allows for quick setup and breakdown
  • 2 stake loops; 1 guyline loop
  • Weighs: 1 lb. 2.6 oz. with pole and 1 lb. 0.8 oz. without


View all Outdoor Research Bivy Sacks

Technical Specs

Best Use



3 - 4-season

Sleeping Capacity



With pole: 1 lb. 2.6 oz.; without pole: 1 lb. 0.8 oz.

Packed Size

3.5 x 12.25 inches

Bivy Length

83 inches

Shoulder Width

28 inches




Contains materials that meet the bluesign® criteria

18 reviews with an average rating of 3.8 out of 5 stars

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