A little extra warmth makes every day more comfortable. The Heat Holders® Men's ULTRA LITE™ Clive Block Twist Crew Sock is 3x warmer than a standard cotton sock. Made with advanced thermal yarns that are long looped and intensely brushed, they're incredibly soft on the inside — trapping warm air next to your skin to keep your feet warmer for longer. A bold block twist design pairs with almost anything. Stay-up, non-constricting fit stays comfortable all day, and the crew length adds coverage right where you need it. ULTRA LITE™ socks are made in our thinnest profile and are perfect for tighter fitting shoes like dress shoes. Just drop in the washer for convenient care.