Avoid sunburnt arms with this long sleeve that looks and feels great on anyone. Riley approved, he wears it ALL THE TIME.
Cotton. For guys, these FIT TRUE TO SIZE (if you wear a L usually, then buy a Large). They're not too tight, not too loose, they've got just enough roominess without being boxy.
They're really soft, not too thick (can wear on windy/cooler summer days and nights) but still great for winter wear. )
Ladies, size down one unless you want it super roomy.