Remedy Calf Sport Compression Running Sleeve Socks: * Nylon/spandex fabric * Moisture wicking * Small fits women shoe size 4-5/ankle size 6.5-8.0/calf 10.5-14.5 * Small fits men shoe size up to 7/ankle size 7.5-8.5/calf 11.0-15.0 * Medium fits women shoe size 5.5-7.5/ankle size 8-9.5/calf 11.5-15.5 * Medium fits men shoe size 7.5-10/ankle size 8.5-9.5/calf 13.0-17.0 * Large fits women shoe size 8-10.5/ankle size 9.5-11/calf 12.5-17 * Large fits men shoe size 10.5-12/ankle size 9.0-11.25/calf 14.0-18.0 * Extra large fits women shoe size 10.5+/ankle size 11.0-12.5/calf 13.5-17.5 * Extra large fits men shoe size up to 12.5+/ankle size 11.5-12.5/calf 15.0-20.0