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REI Flash 45 Pack

trekking poles tipgrips (Parrot/Spritz)
trekking poles tipgrips (Parrot/Spritz)

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


  • Activflex LT perimeter frame combines tubular aluminum with flexible Delrin® side rods to allow torso rotation, yet efficiently transfer the load to the hipbelt
  • Freeflow LT back conforms to your back and has ventilation channels and a central breezeway to keep you cool
  • Streamlined shape fits close to the body for stability; over-the-top compression strap snugs loads close
  • Stretch front stash pocket accommodates bulky gear; mesh side pockets are perfect for water bottles
  • Tip grips are paired with speed hooks to securely hold trekking poles; pack also has multiple lash loops
  • Hydration-compatible design accepts most popular types of reservoirs (sold separately); you can route the sip tube over either shoulder
  • Stretch-mesh shoulder-strap pocket fits a camera
  • The REI Flash 45 Pack also includes handy hipbelt pockets where you can stash small trail essentials


View all REI Backpacking Packs

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Best Use Backpacking
Frame Type Internal
Ultralight Yes
Gear Capacity (L) 45 / 50 liters
Gear Capacity (cu. in.) 2,746 / 3,051 cubic inches
Weight 2 lbs. 2 oz. / 2 lbs. 3 oz.
Weight - Metric 0.96 / 0.99 kilograms
Fits Torso 17 - 19 / 18 - 20 inches
Fits Waist/Hips 28 - 44 / 30 - 46 inches
Material(s) Nylon
Frame Material Aluminum
Number of Stays 1
Pack Access Top
Number of Exterior Pockets 3 + main compartment
Gender Unisex

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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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