adidas Rivalry Baseball OTC Sock (2-Pack) 93% Polyester/4% Spandex/3% Nylon Imported Climalite Moisture Wicking Yarns Help Keep Your Feet Cool And Dry Arch And Ankle Compression For Added Stability Cushioned Foot Provides Protection From Impact Available in 4 sizes: X-Small fits youth shoe sizes 9C-1Y. Small fits youth sizes 13C-4Y. Medium fits Men's Shoe sizes 5-8.5, Women's Shoe sizes 5-9.5, & youth shoe sizes 4Y-6. Large fits Men's Shoe sizes 9-13 & Women's Shoe sizes 10-12