The Under Armour Men's ColdGear Long Sleeve Compression Shirt combine lightweight comfort, breathable performance, and easy mobility in a streamlined athletic design. The original performance baselayer that keeps you warm when it's cold. Our long sleeve mock neck shirt with a compression fit that makes you feel strong, agile, ready and a brushed inside that wicks away sweat and dries fast. Wear it under your uni, your hoodie, your jacket. Or just on its own. Dual-layer fabric with an ultra-warm, brushed interior & a smooth, fast-drying exterior Material composition includes 87% Polyester/13% Elastane. Notable features include Stretch-mesh back & underarm panels provide strategic ventilation without sacrificing warmth; 4-way stretch material moves better in every direction; Material wicks sweat & dries really fast.