The Heat Holders Rook Block Twist Crew Sock for Men feature the same warmth and comfort as the ORIGINAL Heat Holders Crew sock, but with a striking and fashionable block twist design! Thick, chunky, and with a massive tog rating of 2.34, Heat Holders are made from a specially developed heavy bulk yarn which has extreme thermal qualities. With long pile cushioning, these men's thermal socks will help keep feet fully comfortable and supported. The inside of each sock has been intensively brushed such that they not only feel sensationally soft but also trap warm air close to the skin keeping your feet warmer for longer. Non-binding. They are diabetic friendly and provide relief for cold feet due to circulation problems. 91% acrylic/5% nylon/3% polyester/1% spandex. Machine wash. Imported. 91% acrylic/5% nylon/3% polyester/1% spandex Tog rating of 2.34 Long pile cushioning keeps feet comfortable and supported Intensively brushed for softness Non-binding Diabetic-friendly