Review: Mammut Rime IN Hybrid Flex Jacket

We all have that jacket. We’ve worn it on our highest summits and in our lowest valleys. It’s kept us dry and warm, and is the perfect pillow when no other options exist. Life outside is intertwined with a reliance on the clothing we wear. Mammut have done it right with the Rime IN Hybrid Flex Jacket, I’ve been living in it for the last few months and it has become that jacket.

Features, Materials and Technologies:

  • Weight: 336 grams
  • 100% polyamide lining
  • 100% polyester filling
  • 94% polyester 6% spandex insert
  • 60 gram fill Toray stretch insulation
  • Pertex Quantum Air fabric
  • Ajungilak comfort technology
  • 2 large hand pockets, 1 inner drop pocket
Nat in front of Mount Hooker, with Nalgene in front Pocket! – Photo: David Cook


Due to a combination of technology and craftsmanship, the Rime IN Hybrid Flex Jacket thrives in the gritty lifestyle of the everyday adventurer. The Pertex Quantum Air fabric shines, providing a balance between breathability, durability and warmth. The answer to layer anxiety lies within this blue collar jacket—it handles the West Coast downpours, battles the Wind River Range’s namesake winds and remains wearable when approaching in weather due to its wicking ability. In addition, its low profile allows it to be worn as a mid-layer under a shell. This is where the Ajungilak technology is a great addition to the jacket. Typically used in Mammut’s sleeping bags, the light fill used is warm enough to keep the chill off all night during unplanned bivouacs… tried and true on Mount Stuart.  

We love the pockets of the Rime IN Hybrid Flex Jacket!
We love the pockets of the Rime IN Hybrid Flex Jacket!


Most technical climbing jackets have the above features. The Rime IN Hybrid Flex Jacket is tailored to be a tool, evident by multiple additions that make a world of difference.

While in the Wind River Range, I noticed that the front pockets fit completely unencumbered above a harness, and a 1L Nalgene fits comfortably in the pocket. This is huge for alpine missions. In tight chimneys your trusty bottle may have to go in a bag, but for rambly terrain it felt much more comfortable than having my water clipped to my harness and the convenience of having water accessible at all times is not lost.

The only thing that Mammut overlooked is the design of the cuff. It has a comfortably stretched elastic, but isn’t adjustable. I find that I have to literally roll up my sleeves to be able to use my whole hand, especially when crack climbing. A cinch would fix this issue.


Mammut lists the Rime IN Hybrid Flex Jacket at US $249, a comparable price to similar jackets. Patagonia lists their Nano Air at US $282, and the Arcteryx Atom sells at US $239. If you’re in the market for a mid-layer that can double as a shell, it is a worthy investment.

Notice the rolled cuffs, they are a little inconvenient but manageable, and a tiny downside. Photo: JP Melville
Notice the rolled cuffs, they are a little inconvenient but manageable, and a tiny downside. Bottom belay zipper also featured.


The Rime IN Hybrid Flex Jacket is a workhorse. It has taken a beating and proved its durability after intense use. When cragging on a rainy day in Squamish, or waking up early for an alpine mission in the Bugaboos, this jacket simply works. The cuff is the only issue that I can find, and even then it is a nitpicky one. To the minimalist adventurer that looks for multi-faceted tools, look no further.

Pros: Comfortable. Durable. Remains as waterproof and windproof as advertised.

Cons: High price point. No cinch on cuff.

Overall: The Hybrid flex quickly became my personal go-to mid-layer. That one jacket that I grab for almost every occasion and weather condition. A solid piece that won’t disappoint.



This Review was written by: Nat Bailey

Black Sheep Adventure Sports was provided with a sample jacket for testing but of course this didn’t influence us in any way.

Cover Photo: JP Melville