The Incrediwear Sports Socks relieve aches and fatigue when spending long hours on your feet or participating in multipurpose activities such as tennis, hiking, training, etc. The Sports Socks are anatomically designed for left and right footing with cooling toe box and heel cups to provide maximum comfort throughout the day. SIZING: Based on shoe size. (All socks are final sale.) S: 35-38 M:39-42 L43-46 TECHNOLOGY AND SPECS: Incrediwear?s signature fabric blend is embedded with semiconductor elements to provide effortless comfort and exceptional durability Effortless comfort Wash and Care Instructions: The Incrediwear Sports Socks are easy to clean. Wash warm or cold. Tumble dry low. Do not bleach, iron or dry clean.