I bought thinking I might wear it on chilly mornings. I ended up wearing it all the time. I love this shirt. I wear it in the pool, at the beach, on the boat and now stand up paddling. It is just enough thermal protection. I also wear it under my 3/2mm wetsuit to make it warmer in the winder. Great cut and stretch. The size chart was nice. I was inbetween sizes and went up and I am happy with my size.