Heat Holders Worxx® Men's Big/Tall SocksReinforced heal and toe for durability Extra large size Advanced thermal yarn More than 7X warmer than a basic cotton sock! Sensationally soft Non binding All the same warmth and durability as the original Heat Holders Worxx Crew sock, but in an Extra Large size. Keep feet warm on the coldest of days and pull on this pair of solid color, extra large, crew length, reinforced Heat Holders for men, the warmest thermal sock. Thick, chunky and with a