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Climb like a mutant.

High on a ridgeline, winds swirling around your perch, the stability of your pack and gear is of paramount importance—that's why a pack like the Osprey Mutant 38 Backpack is so important. Support and stability come in the form of a removable HDPE framesheet, a removable aluminum stay, and an AirScape back panel that also ventilates as you climb. This top-loading pack features a removable floating top lid to lighten your load for summit day. When removed, you can protect and secure your gear with the FlapJacket closure system. 

To help you haul everything you need, Osprey added its Mutant Dual ToolLock ice-tool system that lets you securely carry, and remove, tools when needed. Side compression straps let you secure your load if it's not quite full, and the A-frame ski carry makes sure that you can get down off the top the fun way. To help keep you from overheating on the way up you can store your helmet in the removable helmet-carry system up top.

  • Reverse wrap hybrid EVA foam hip belt
  • Removable 1.2mm HDPE framesheet
  • Removable aluminum stay
  • AirScape back panel
  • 35-50lb optimum load range
  • Top-load access
  • Removable floating top lid
  • Nylon and polyester
  • FlapJacket closure
  • Internal hydration sleeve fits up to 3L bladder (reservoir not included)
  • Zippered top pocket
  • Zippered mesh pocket under FlapJacket
  • Mutant Dual ToolLock ice-tool system
  • Integrated gear loops on hip belt
  • Side compression straps
  • A-frame ski carry
  • Removable helmet carry system

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Here's what others have to say...

What size will fit an 18" torso? It looks like the size chart is slightly out of date for this model. The newer versions is only offered in two sizes instead of three.


The S/M is the size you'll want for an 18" torso.

S/M is 15-19"

L/XL is 19-22"

Hope this helps!

Shoot me an email anytime you have questions!

Jared D.

Expert Gearhead