Made from 91 percent polyester and 9 percent spandex, the stretchy shirt is comfortable in high temperatures, wicks away moisture and dries quickly, whether you’re using it on the water or just hanging it to dry in your hotel room. Icefil technology in the fabric cools skin (up to 5 degrees) upon contact with moisture. The slick fabric may snag if you’re wearing the shirt around rough surfaces that you’re scraping up against, like rocks.