Under Armour Women's ColdGear Elements Mock 87% Polyester/13% Elastane Imported UA Storm 1: Water-resistant arm & neck panels Dual-layer fabric with an ultra-warm, brushed interior & a smooth, fast-drying exterior ColdGear Infrared technology uses a soft, thermo-conductive inner coating to absorb & retain your own body heat Mesh under arm panels to dump excess heat Material wicks sweat & dries really fast