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REI Ultra Dog Pack

Spring Moss
Spring Moss

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


  • 100% post-consumer recycled PET body is built tough to stand up to heavy outdoor use
  • Sleek and lightweight cord compression system pulls the pack load up and close to the body for unmatched stability
  • Water-repellant zippers help seal out the elements and protect the contents from moisture
  • Zippered expansion panels let you increase or decrease the saddlebag volume to match your dog's load
  • Zippered top pocket on each saddlebag holds small items within easy reach
  • Harness combines mesh for breathability and padded sections for comfort; perforated EVA foam reduces weight without sacrificing comfort or durability
  • Short lead is integrated into the harness handle to help guide or hold your dog when a longer leash isn't needed or available
  • High-strength aluminum leash ring is easy to grasp while clipping on a leash
  • Harness buckles feature a unique cam lock to eliminate webbing slip even when wet


Sizing is based on girth, which is measured around the widest part of your dog's rib cage.

View all REI Dog Packs

REI membership


Best Use Hiking
Fits dogs 26 - 35 / 32 - 41 / 35 - 46 inches
Gear capacity (L) 7 - 8.5 / 11.5 - 13.5 / 17.5 - 21 liters
Gear capacity (cu. in.) 427 - 518 / 701 - 823 / 1,067 - 1,281 cubic inches
Number of exterior pockets 2 + 2 main compartments
Material(s) Recycled PET
Dimensions 9.5 x 6 x 4 / 10.5 x 8 x 4.5 / 12 x 9.5 x 5 inches
Weight 1 lb. 2 oz. / 1 lb. 5 oz. / 1 lb. 6 oz.

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100% satisfaction guaranteed

We stand behind everything we sell. If you are not satisfied with your REI purchase, you can return it for a replacement or refund within one year of purchase.

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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At REI, we live and breathe the outdoors, and we're passionate about sharing our expertise with people of all skill levels. Whether you're new to the outdoors or a seasoned explorer, we'll take the time to understand your needs and help you find the right gear for you.

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*10% is typical but not guaranteed. Your refund is based on eligible purchases, which exclude REI gift cards, services, fees, REI Adventures trips,, and discounted items. Learn more