A classic thermal layer built with proven waffle-knit cotton, our Union Suit is the baselayer for warmth in frigid weather. With one-piece construction, there are no gaps in insulating coverage from neck to ankles, and the deep channels in the fabric excel at trapping heat close to the body and moving moisture away from your skin. The front buttons from neck to waist for easy on/off as well as torso ventilation during high exertion. Sturdy rib-knit cuffs at the wrists and ankles have excellent memory for shape retention. Large button-close back opening.