Pretty simple shirt. I'm a chick so it's bigger for me but it fits, small as always. It runs slightly longer than most other small men's shirts. I can't tell if it's actually merino, but it was warmer than my other cotton shirts, so maybe? It's very thin, like a regular shirt, so I can't tell. If I can trim it myself and it doesn't look silly, I'll buy more for work. It's warm enough under the sweater and when I go home I have enough air on me so I don't sweat like crazy.