Orvis Men's Heavyweight OTC Wader Fishing Sock - The merino wool Heavyweight OTC Wader Sock is the definitive answer to warm, dry feet for winter fishing. Made of wool, nylon and spandex. Heavyweight warmth, sewn from high-density merino wool Over-the-calf height Perfect fit and patterned after Orvis wader booties and boots Reinforced zones in heel, toebox, and top of ankle Ribbed arch eliminates bunching Sizes XS-XL. XS (Men's 2.5 - 5, Women's 4.5 - 7), S (Men's 5.5 - 7.5, Women's 7.5 - 9.5), M (Men's 8 - 9.5, Women's 10 - 11.5), L (Men's 10 - 12, Women's 12 - 14) XL ( Men's 12.5 - 14.5) Style: 3A15