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 61% Thorlon acrylic, 37%Thermolite, 2% Spandex Exclusive Thorlon and Thermolite blend for maximum warmth and wicking Thick cushioning in ball / heel for protection and comfort Moderate cushioning in shin /instep protects from boot pressure, and in arch for better fit Ventilation panel for better wicking