SockGuy Classic 5in Belgium Cycling/Running Socks (Belgium - L/XL) 10% spandex 75% moisture wicking micro denier acrylic, 15% nylon, 10% spandex for exceptional comfort and strength Mesh upper above your foot allows maximum ventilation and breathability Easy fit cuff features a non-binding cuff Stretch -to-fit, 2 size system Warm weather sock