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


  • Top material uses a waterproof, breathable coating bonded to a tough yet lightweight ripstop nylon
  • Durashield™ polyurethane coating provides incredible waterproofness on the exceptionally durable nylon floor
  • Factory tape seam sealing provides absolute in waterproofness and out-of-the-store readiness
  • Envelope-style opening overlaps to provide a lightweight and simple entry; zippered mesh panel at the top end provides insect protection
  • 3D footbox provides ample room for campers with large feet, and comfort for everyone
  • Stash up to a medium-size pack in the hood area while you are inside; opening is situated to fit where your face is with the pack at the head for easy access
  • AC-Bivy fits you, your sleeping bag/pad and your pack!


View all MSR Bivy Sacks

REI membership


Best Use Backpacking
Seasons 3 - 4-season
Sleeping capacity 1-person
Weight 1 pound
Packed size 4 x 8 inches
Bivy Length 88 inches
Shoulder width 36 inches
Design type Bivy

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

If your item has a manufacturing defect in its materials or workmanship, you can return it at any time. See our limited warranty.

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