Tesla TM-R11-BKRZ_Large Men's Long Sleeve T-Shirt Baselayer Cool Dry Compression Top R11 We strongly recommend ordering ONE size up what you normally wear. TeslaGears R11designed for all seasons (Releases heat and wicks moisture with a cooling effect) 87% Polyester-13% Spandex Non abrasion fabric material with excellent elasticity and durability Moisture Sensing/Quick time Dry/TWO-WAY Air Circulation.