Under Armour Men's ColdGear Infrared Grid &frac12; Zip 100% Polyester Imported Dual-layer, textured-grid fabric traps heat for warmth with very little weight ColdGear Infrared technology uses a soft, thermo-conductive inner coating to absorb & retain your own body heat Stretch-woven overlays for added protection Material wicks sweat & dries really fast Anti-odor technology prevents the growth of odor-causing microbes