Greenish-gray striped tee in 200 gsm weight merino wool, by Merino Protect brand. This is every so slightly heavier weight than a typical T-shirt, but still good for warm weather. Fit is a little relaxed, and fabric doesn't have much stretch, so it's a roomy size small.  Merino is excellent for travel--you can wear this shirt for days on end and it won't hold on to odors (just let it air out overnight). This shirt is 100% merino wool, no blends.