Meet the Womens Classic Thermal Merino Base Layer Crew One Piece, which provides a full-body layer of warmth. This 100% Merino wool one piece combines the moisture management, temperature regulation, and odor resistance of Merino with the comfort of an interlock knit. Featuring a fully functional fly, a zippered drop seat, set-in sleeves, and a flatlock seam to help prevent chafing, this base layer is designed for easy wear and maximum comfort.