DetailsLasting Size Chart A versatile sock made from a single layer plush knit. 60% of the sock is made of COOLMAX - polyester material, a special, non-absorbent four-channel polyester fiber which removes moisture from the surface of the skin to the top layers of the sock. The heel and toe is reinforced with a double layer plush knit, which has been designed to provide better thermal insulation and protection against blisters. The siltex material has antimicrobial silver ions. Elastic is fitted around the instep area.