Perfect thickness...not too clingy and very breathable. I ordered this one and a Dakine midweight. The Dakine shirts defintely run a lot smaller than the Burton and are a lot more form fitting. This shirt can be worn as an underlayer or with jeans. It may run a bit on the big side...so if you're looking for something really clingy and form fitting I'd suggest going with the Dakine midweight rather than this one.