This is a 2XU singlet. I only tried it on (the tag has been cut off, so it's not included). The Light Speed Tech Singlet, made with super lightweight, moisture-wicking material, features ventilation zones in key areas to enhance heat radiation and breathability during running. Ultimate Comfort Mesh ventilation zones are placed on the chest and back to keep the areas that need it most cool while running. Ultra-Lightweight Ultra-lightweight engineered construction with clean-cut bonding on key areas for a smooth finish that allows for free movement. Quick-Drying Ultra-fine polyester yarns quickly disperse moisture, keeping you cool and dry. Reflective Trim (Safety) Reflective logos and trimming on the shoulders, upper back, and hem. Material Composition 100% Polyester