Photos & Words: Simon Pitman

The fifth generation of one of Osprey’s best sellers, the Mutant 38 is a lightweight and versatile alpine rucksack that is built for all-year round ascents; blending a minimalist design with impressive weatherproofing.

We gave the pack to our Fort William Store Manager, Simon, to put it through its paces and see if it lives up to its impressive reputation.

Initial thoughts about the rucksack

It looks great! The old version of the pack was versatile but had lots of straps hanging off. Osprey have managed to keep the list of features high, while making the pack cleaner.

Key Features

  • Ultra-durable 420HD nylon pack cloth and 210D nylon honeycomb fabrics
  • Snow-shedding back panel
  • BRemovable HDPE frame sheet with T6061 aluminium stay for support
  • Low-profile, non-restrictive harness with load lifters
  • Adjustable sternum strap with emergency whistle
  • Reverse wrap stowable hipbelt
  • Integrated gear loops on hipbelt for easy racking
  • Removable lid with dual compartments
  • Integrated ski/climbing helmet storage
  • FlapJacket cover for use when lid is removed
  • Under lid rope carry system
  • Internal hydration sleeve
  • Dual ToolLock ice axe attachments
  • Dual front daisy chains offer flexible attachment options
  • Side ski carry
  • Side compression straps
  • Glove-friendly buckless
  • Weight: 1.26kg (0.82kg stripped weight)

Snow shedding back panel and straps

The moulded back panel, shoulder straps and hip belt are covered with a durable fabric outer that passively sheds snow, keeping you warm and your pack as light as possible.

Snow shedding back panel and straps

Dual Tool Lock

A quick and easy to use ice axe carry system, that is glove friendly; it securely holds two axes to the back of the pack. When you’re ready to use them again simply twist and unlock the tool pulleys and you’re ready to go.

Osprey Mutant Dual Tool Lock

External Helmet Carry

The top lid hides an elasticated helmet net that is a great for storage when moving between pitches.

Osprey Mutant helmet storage

Flapjacket top cover

For shorter climbs or lighter loads, you can detach the top lid while retaining a weatherproof closure. The flap jacket is neatly tucked away behind the drawstring opening where it unravels to cover the top of the pack.

Flapjacket top cover

How did it perform?

Osprey Mutant being tested

Comfort: 8/10

The straps are good at dispersing the load, although some people may feel the padding is a bit thin. However, the trade-off for snow shedding is worth it.

Pockets: 9/10

Almost perfect for me. Which is to say there’s few two zip compartments; one on the lid and a small one on top of pack with a clip for keys in.

Features: 10/10

The features on this bag make it, in my opinion, one of the most versatile bags we stock.

Ventilation: 7/10

I had my doubts when seeing the back system, but breathability is adequate when working hard.

Weight: 7/10

It’s on the heavier side but that’s the price you pay for features. Plus, if you’re doing a lightweight mission you can remove the lid and frame, dropping weight from 1.26kg to 820g.

Versatility: 10/10

The most versatile bag we sell. This bag can be used as a fast and light ascent pack, or for multi-day technical routes. Take it ski touring, ice-climbing, trad or sport climbing, or even scrambling! It does it all.

Sizing: 9/10

True to size and easy to adjust.

Materials/Durability: 9/10

Rucksack fabrics have really improved in recent years and this bag proves it with durable but ultra-light outer.

Aesthetics: 9/10

Clean and modern for a simple understated look.

Pros & Cons


  • Versatile
  • Comfortable
  • Well thought out features
  • Can be used year round


  • Weighs slightly more than minimalist packs

Overall Verdict

A great update for the Mutant. It’s an excellent choice for those wanting to buy a bag that can go with them on any outdoor adventure. If you’re happy with a bit of extra weight, the feature set is well worth it.

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