Thorlos Unisex SL Ski Padded Over the Calf Sock 77% THORWICK WARM acrylic, 20% nylon, 3% spandex Turn Inside Out-Machine Wash-Use Liquid Fabric Softner Thin cushioning in ball and heel for warmth, shear protection and comfort Thin cushioning in shin and instep to protect against shin bite Flat knit instep and arch for better fit and ventilation Exclusive Thor Wick for maximum wicking because a dry foot is a warm foot