This is snow wear from Turtoise, a surf brand from Kamakura. The size is S, but it fits a bit roomy on me, and I'm 170cm tall and weigh in the low 60kg range. It feels good, so I think it's safe to assume it's equivalent to a size M. I bought it used and have only worn it a few times. I'm selling it to clear out some space because I'm going snowboarding less often these days.