These socks are great for a snug fitting ski boot. They have just enough stretch to fit comfortably without slipping around or bunching up when you put your boots on. These are pretty durable considering how lightweight they are. These hold their shape and size well even through several washings.

Works well under cold conditions.

I bought these for my wife only to have her discover they have far less stretch than the "regular" SmartWool PhD Ski Ultra Light Sock (the one you may consider the men's SmartWool PhD Ski Ultra Light Sock; I contend that, in light of the fact that those have women's sizing listed on them along with men's sizing, they are not men's but rather they are intentionally unisex). If you check out the materials, you'll see that they're not the same. My wife is athletic and has actual calf muscles and these socks don't work for her but the unisex ones work great. Buyer beware.

Measurement and sizing information listed with this review pertains to my wife.

Wore these socks for the first time last weekend snowshoeing. Temperature was around 20 degrees outside and my feet stayed toasty warm the entire time. I prefer a thinner ski sock and these are perfect. My shoe size is a women's 6.5 and the medium sock fits well, just a little extra room in the heel.

You really cant go wrong with a SmartWool ski sock, they are my favorite brand by far and the patterns are great! I love how thin these are, and although they are thin still do a great job of keeping my feet toasty all day. My feet don't get cold too often when I am skiing, but if you find your feet do I would recommend the medium thickness sock.