Copper Sole Mens Outdoor Hiking Acrylic/Wool Blend Crew Sock, CS503DG 48% Acrylic, 20% Merino Wool, 19% Nylon, 12% Copper Polyester, 1% Lycra Spandex. Made with an acrylic and soft merino wool blend for added warmth and comfort. The reinforced heel and toe adds to the durability of an already durable sock. Arch support and smooth toe seam protects and comforts the foot. A perfect work sock or boot sock!