The Dakine Highback Sock is a medium to heavy weight sock constructed with the highest quality merino wool, acrylic, stretch Nylon and Lycra spandex to offer the best balance of warmth, comfort and wicking ability. Multi-density knitting provides warmth and cushioning to areas that need it most. Reinforced heel and toe for durability. Compression zone at arch. Shin, heel, and toe padding. Material: Wool, Acrylic, Polyester and Nylon.