Very warm, and really kept the dust out of my face, while in the desert. Everyone was jealous of it. Sometimes is a bit tight around the neck, but compared to the rest of the Carhartt products I own, it's definitely one of the best.
The only problem I had with this was the tag. When I first tried it on there was a large tag that was very rough and stiff on the inside that did not feel great on my neck. After some careful removing to not damage the stitching of the item it is much more comfortable. I have used a few different versions of these or similar items for skiing but those are usually a more lightweight material. For long hours working outside in the cold this one is a much thicker fleece instead of a polyester material so it seems like it will be warmer (although also more bulky) and will hold up well but I have not had it long enough or used it enough to really rate on durability or quality but it seems like something I will have for a while.
It does it job by keeping you warm especially on those cold windy days. It's great when your not doing alot of work but once you get moving or working it gets really hot so I have to take it off. The only complaint I have is if your going to use it as a face mask it's not long enough and a small draft goes down your neck on the bottom of the gaiter. If it was just slightly longer I would give this five stars but other than the length it does its job.
You can pull it on over your head (It will mess up your hair). Then as it is around your neck, it can stay up over your mouth if you want it too. It does have a stretch to it. Mine measures 10.5" across so double that will give it 21" in circumference. Works great and I love it for work.
I don't have it with me to measure but it is smaller than other brands I own and I actually don't use it because it's too small. If I were you I'd get the measurement from the company before you order. I probably should have returned mine. The fabric is nice. Too bad it is small.