I have just received a medium. I tested it out but not convinced. It is a little snug in the chest area. I'm 5'3" 131 pds 36D. I feel it is more of a trim fit than a standard .You cannot put layers underneath. The body is warm, however the sleeves will probably not be good below 0C or 32F unless the sun is shining and there's no wind. My son described it as a vest with sleeves. I feel that's a good description. I like the length. Covers your bottom. The hood is nice as well. Would only recommend to friend if they were looking for a vest type jacket and they weren't chesty.