UPF 50 certified sun protection against ultraviolet (UV) radiation produced by the sun. Fabrics are tested for UV protection in accordance with international standards. HeiQ Smart Temp is an intelligent thermo-regulating technology for fabrics, which is triggered by body heat to maintain optimal body temperature. Made with 95% of recycled content. Feels light and dries fast for freedom and comfort. Ultimate stretch and seamless comfort that moves with you.