I bought this base layer for a ski/boarding trip and felt it worked fantastic to keep me warm. Love the zip on it; felt kind of tight at first but ended up working out well after layering. I am guessing this is part of the design as well as helps to trap heat. Not only does it function very well as a base layer it also looks very nice and compliments a woman's figure. I would suggest this base layer to anyone looking to ski/board at colder times or if you want to only wear a light base layer and a wind breaker during spring skiing. Great buy!