Love the pattern and the design, very lightweight. But I think the sizing is a bit off. I'm 59", 170 pounds, and the medium fits so tight on my chest I can barely zip it. Also bought the mountain pants, and they are awesome.

Really lightweight but very warm nice fit. Except wish it was longer.

I want to start this review by saying I had very high expectations for this jacket. From what I had seen in videos and read this was supposed to be the ultimate insulation layer, keeps you warm when stationary, but breathes very well when active. Well upon receiving it the first thing I noticed was how lightweight/thin of a jacket it was this gave me my doubts. Then I had a chance to use it for a late season elk hunt in western Washington. 4 out of 4 stars! This did not disappoint at all! I put it on in the morning and never took it off. It was exactly what I was hoping for, can definitely feel the warmth when you're wearing it and is great under the Thunderhead jacket. I even wore it to sleep in for added warmth. But I never got too hot when wearing it solo or layered. Idk how they did it but it's great. The body is a little short but it was made this way so it isn't sticking out underneath other jackets when used as a layer. I'm 5'8" with athletic build and with Sitka performance fit I wear a large and this fit the same. Great jacket, I highly recommend it.

Just a regular dude here. The hype is real...Soft, quiet, drys quickly, and is lightweight. Makes a great pillow in the sleeping bag. It's almost like a really intense base layer in the sense that it's warm, but wicks away moisture. It's bizarre; no other jacket like it and I recommend you check it out.

Not sure how they do it. I have the Kelvin Lite, the Kelvin Ultra Down, and the Kelvin Active. All excellent pieces and all seem to be designed for something different. I didn't think it could get any better than the Kelvin Lite. Then the Kelvin Ultra Down came out. My absolute favorite piece. Being a little skeptical of their newest piece, the Kelvin Active jacket, I put it to the test. The previous pieces are mostly design for low activity to no activity. The Kelvin Active jacket somehow keeps you warm with low activity and vents heat during high activity without sweating. No clue how they do it but this jacket is a killer at have. Warmth without overheating.

This jacket is AWESOME! Was super excited about it when I tried it out at the Western Hunt Expo and it lived up to the hype. Wore it for two weeks while guiding wilderness hunts and it is probably my most favorite new piece of gear. Plenty warm as a stand alone outer layer even on cool mornings riding in on horse back and combined with decent rain gear, it's a perfect mid layer. Dries out quick and seems to help keep my base layer dried out as well. Going to be even better during the rifle seasons underneath my Jetstream jacket.

This thing is awesome. You can go uphill all day, and never be too hot or too cold. Dries like a dream and makes a great pillow...what more could you ask?