Exclusive THOR-LON® construction for resilience, durability and better wicking.X-Static® -The Silver Fiber is knitted into the foot area to provide permanent anti-microbial and anti-odor benefits.Moderate cushioning in ball/heel reduces shock, impact and blisters.Thin cushioning at instep for lace pad protection.Spandex in arch for better fit.Fiber Contents: 77% Exclusive THOR-LON® Acrylic, 12% Stretch nylon, 5% Spandex, 6% X-StaticSize 9 (Womens 4-6)Size 11 (Mens 5.5 - 8.5; Womens 6.5-10) Size 13 (Mens 9 - 12.5; Women's 10.5 13)Size 15 (Mens 13-15)