Featuring an anatomic and ergonomic fit, SLAM's Thermalite top can be worn as a first or second layer. The fast wicking material quickly moves moisture towards exterior, while maintaining comfort and body. Thermal regulated Bacteriostatic technology blocks bacterial proliferation that is harmful for the skin’s health by assuring its physiological equilibrium and its natural transpiration. Internal anti-ride silicon grip on trim and flat stitching with double hold. 95% Polypropylene 5% Spandex.