As vital as board shorts and ice on a Baja surf trip: Patagonia's quick-to-wick, quick-to-dry tee keeps you cool, dry and moving freely during active pursuits. Made of a 5.1-oz 84% polyester/16% spandex blend (their stretchiest baselayer fabric) with Gladiodor odor control and 50+ UPF sun protection. It rests lightly on the skin, allows a cooling airflow, and wicks perspiration. Offset seams feel smooth under pack straps, and reflective logos on the chest and center-back add visibility to predawn runs.