Using yarns that have excellent thermal properties combined with the specialized manufacturing techniques employed, the result is the warmest thermal sock imaginable. You deserve comfortable socks and these are them. The inside of these heavily brushed lined socks are are soft and comfortable. With the inherent moisture management of these socks combined with the thermal properties, the result is a fantastic performing sock, the warmest thermal sock imaginable. Fits men's shoe size 6-12, sock size 10-13. 94% acrylic/5% polyester/1% spandex. Machine wash cold, tumble dry low.