Kit Review: Mens Anti-Freeze Down Jacket

Mountaineers Matt Cooper and Jack Thompsett share their verdict on the mens Anti-Freeze Down Jacket. See how it shaped up taking on the mighty Swiss Alps…

With no easy way up the mountain and no lifts, I knew that carrying minimal weight and being able to trust our kit would be key - which made this a perfect objective to test the Montane Anti-Freeze Down Jacket.” Matt Cooper

Based in Wales, full-time mountaineering guides Matt Cooper and Jack Thompsett are regularly found guiding on some of the best mountains in the UK. However this summer the dynamic #TeamMontane duo set their sights a little higher, heading out to the Swiss Alp for several months. Their mission? To climb several 4000m peaks, including Zinalrothorn (4221m) - a peak Matt’s had on his radar for many years now!

No strangers to adventurous routes at high altitude, both Matt and Jack understand the importance of specialist kit to match their needs. Lightweight kit without compromise is essential for those seeking to confidently explore these challenging environments. Cue the Mens Anti-Freeze Packable Down Jacket - a lightweight companion that helped to keep them well protected on bitterly cold Alpine bivvies and remote snowy summits…

First Impressions

Matt: Anybody who climbs at altitude will know that every gram counts and a heavy pack is no fun, especially when you need to carry it all uphill. The Montane Anti-Freeze Down Jacket is by far the lightest most packable down jacket I’ve ever used (460g) and once it's compressed into the stuff sack, it was barely noticeable in my climbing pack. I also needed the confidence that it would be durable and offer warmth, but not be sweaty or hold in the moisture. I was pleasantly surprised that despite the small pack size - the warmth and loft of the jacket was incredible and it allowed moisture to wick away from the layers, much needed when climbing in the dark at 4000m.

Jack: Right out the package the vibrant colour delivered a bright first impression! (If bright colours are not your thing, there is a huge selection from black to adrenaline red). Smoothly zipping the jacket up, the comfort and insulation are noticeable immediately. Easily stuffing the down jacket into the supplied bag provides you with a very small package. For the size the Anti-Freeze compresses down to it certainly packs a punch. Packable is the name and packable certainly is its game! 

How did you test the Jacket?

Matt: Zinalrothorn is a 4221m peak in the Swiss Alps and the needle-like summit is a test for any mountaineer. While the Alps have been warm this year the morning of our ascent the temperatures dropped well below freezing so we needed a jacket we could wear on the move until the heat started to build at sunrise. The conditions, harsh environment and our fast and light approach made this the perfect day to test out the new jacket and see how it performed on a high-altitude peak.

Jack: I’ve used the jacket for four months of full time use, alpine climbing in the Swiss and French Alps. The Anti-Freeze Down Jacket provided a reliable partner for long and committing Grande courses, to cold 4000m peaks. In remote environments like this it is essential to have kit you can trust, so you can confidently explore into the unknown. It got tested in a full range of weather and situations: from sleeping in it during Alpine bivvies, where it’s common to wake up slightly damp from dew to taking the full brunt of bone chilling -15 degree C winds on high summits! 


Matt: I’m 5’8” and found the small jacket was perfect for me. The jacket comes a little larger which is perfect when you’re wearing layers underneath but not baggy. I would probably describe the fit as comfortable, but not tight and close fitting where you need it, like the arms and chest.

Jack: I’m 5’11” tall, with wider than normal shoulders and a slim waist (29 inch), I’m usually between a small and a medium in Montane clothing. It offers a very functional design for the mountains due to the long arms, a large hood, a slim but long fit and generously sized pockets. The medium size has allowed me to use it as an outer insulation layer during the summer months, but has also worked perfectly as a mid-insulation layer as temperatures are dropping this autumn. The Anti-Freeze also looks just as at home in the mountains, as it does accompanying you to the pub!

Favourite Features

Matt: A key feature for any down jacket I use is the ability to pop a helmet over the hood! Montane have clearly put a lot of thought into the jacket as the hood fits perfectly around the helmet, a great way to keep your head and neck warm on cold alpine starts.

The cuffs and waist are all elasticated which is ideal when you need to keep the heat inside and the drawcord on the waist is easy to use with gloves. Nothing worse than losing all the hard-earned heat from the jacket when the wind blows, the Anti-Freeze worked perfectly when the morning breeze started picking up.

Jack: My favourite feature has to be how packable the jacket is. It makes the decision very easy whether you’re going to take this jacket with you or not as you just don’t notice it in your bag. It does this without compromising its warmth, which for me is a big win! 

Montane have used water resistant down in the Anti-Freeze (90/10 water resistant fluorocarbon-free HyperDry down), which is a great bonus, while using it while bivving, or having piece of mind if the odd shower is forecasted. I have also been impressed with the durability, four months of use and many big alpine routes, the Anti-Freeze is coping very well. Virtually on a weekly basis I’m using tape to repair kit which has been torn while out on adventures, so far the jacket is completely tape free, which is very impressive! 

Overall Summary

Matt: The Anti-Freeze Down Jacket works is the outer layer I pair with my overall layering system and is worn over the Montane Dart Base Layer and Protium Fleece. The combination of these allowed any moisture to wick away from the skin and permeate through the layers, so we didn’t feel sweaty when pushing hard on the steeper sections.

As we approach winter I can see numerous uses for this jacket and it's certainly become a favourite. A warm jacket for winter bouldering, a belay jacket for Norwegian Ice Climbing or just a cosy jacket for the pub or winter beer garden, I see no end to the places or environments this jacket could be used. Perfect when you're heading into the outdoors finding your unknown.

Jack: Throughout the summer I’ve paired the Anti-Freeze Down Jacket packable mostly with the Dart Long Sleeve T-Shirt and Allez Micro Fleece Hoodie. These products proved a great combination for summer Alpine climbing, the under layers also being light and warm. I look forward to using this jacket over the coming winter, particularly as a mid-layer for Scottish winter climbing, where the water resistant down will come into its own! I can also see it working really well for my ski touring and Alpine climbing missions, where weight to warmth ratio is hugely important!

Feeling Inspired?

Matt and Jack reviewed the Mens Anti-Freeze Packable Down Jacket, which is also available as a Womens Down Jacket. For even more down jacket options, suitable for a wide range of activities - including hiking and climbing - see our entire down jacket range