Arc'teryx  Fission SV Mittens

Bought these in Vancouver mid-March 2025. It looks like mine were the version just before the "revised" version came out. There's a tag marked CA#34438. Bought them for pretty much one reason only: I needed a very warm mitt. They might be great in all the other departments, but warm they are not. Tried them this morning for the first time since I bought them. Took the dog for a walk and then stood around talking to other dog owners. Temp was -1C - no wind. Hands got really cold in not a long time. The mitts fit perfectly: XL for my hand size. This is my first Arcteryx purchase. If it wasn't billed as their "warmest mitt" I probably would not be posting this. I hope the revised version is better; it will have to be a lot better to even come close legitimately claim to be warm. Can't imagine how poorly they would have fared in really cold weather. 3 stars overall because of zero for warmth. As far as I can tell everything else is great. Jeff

I was looking for mittens that are small enough to hold trekking poles but warm enough to use around 0°F hiking. This is good. Recently I tried these 2 hiking trips that was around 5°F to - 5°F these were warm enough with liner gloves and proper layerings cloths. If you are looking for just warmth, maybe you can find better mittens. But this one is the best mitten I found that I can use my poles comfortably. I wish it's just a little more thicker with more insulation tho. However, overall easy to use, sturdy and warm so far.

FYI, REI is selling an older version of these mittens for the same price as the newer better version. The one selling at REI does not offer 200g of insulation. The new version was revised due to reviews saying they were not warm enough. Go to arcteryx website.

Love these mitts. I hope Arc’teryx keeps making them for years to come so I can always re up and get a pair when mine are done. Warm, dry, good size gauntlet and love the sleek look. That said the inner wrist strap little circle synch is not good. Doesn’t do much coukd prob use something better in there. All in all great mitt though. My friend also has the gloves and they seem great as well.

I was looking for mittens that are small enough to hold trekking poles but warm enough to use around 0°F hiking. This is good. Recently I tried these 2 hiking trips that was around 5°F to - 5°F these were warm enough with liner gloves and proper layerings cloths. If you are looking for just warmth, maybe you can find better mittens. But this one is the best mitten I found that I can use my poles comfortably. I wish it's just a little more thicker with more insulation tho. However, overall easy to use, sturdy and warm so far.

Good waterproof mitt, however for this price and brand name I would have expected a bit more. The wrist straps don't stay on well because it doesn't pinch tight enough and keeps coming loose. Maybe consider upgrading this valuable piece so I dont lose my mitts when I take them off? Other than that, they are warm and keep the snow out for the most part.

All new kit this year and decided to treat myself to some mitts. I get extremely cold feet and hands on the hill and these keep me toasty warm!! Even when I get a bunch of snow inside it with a good rub on the outside it just falls out and still feels warms as the start of the day. Plenty of use already and no signs of wear

Highly recommend these mitts. Extremely warm. The leather plus the goretex makes them super waterproof.

These mitts are incredibly warm while snow blowing in Winterpeg minus 40. Love them!

I'm a ski instructor in the coast range in BC, and need mitts that operate well over a wide range of temperatures, are waterproof, and have wrist loops. The waterproof part, I've learned from many years, just doesn't exist, and I've bought some very expensive mitts from some well known companies trying to disprove it. So far the Fission is so far ahead of anything I've worn in the past, it's like they dropped out of a wormhole from the future. I even had a complete 'Doh!' moment and spilled some water in them while they dangling from my wrists. I steeled myself for the inevitable ice blocks for hands. My hands dried the gloves from their warmth and the gloves breathability. I haven't had them long, so I can't speak about durability, but for usability, if there were 6 stars, these would deserve them.