Under Armour's most versatile thermal base layer, the Base 2.0 Crew is a must-have for any athlete. Lightweight ColdGear thermal grid fabric is specially engineered to keep body heat in, while transporting moisture away from your skin. Ergonomic flatlock seams lay smoothly against the skin for chafe-free comfort. Raglan sleeve construction allows a full range of arm motion while further preventing chafing. ArmourBlock technology helps reduce odor so you stay fresher longer. Fitted close to the body without the constriction of a compression fit. 100% polyester fabric. Imported.