Thorlos Unisex SKX Ski Thick Padded Over the Calf Sock 59% Thorlon Acrylic, 39% Thorwick WARM Polyester, 2% Spandex Turn Inside Out-Machine Wash-Use Liquid Fabric Softner Thick cushioning in ball and heel for warmth, shear protection and comfort Thick cushioning in shin and instep to protect against shin bite Moderate cushioning in arch for better fit with spandex for added support Exclusive Thor Wick for maximum wicking because a dry foot is a warm foot Ventilation panel for better air circulation