Engineered for Performance, Feetures Elite is our most technically advanced sock. Our Elite socks are anatomically constructed using our patent-pending Sock-Lock technology to provide targeted support where it's needed most. As a result of this enhanced fit, the foot and sock become one. Our Light Cushion socks are designed with high-density cushioning that provides extra protection in high impact zones. Light Cushion socks are great for those who prefer cushioned comfort without a lot of bulk. Sizing Instructions - Our socks are unisex and fit according to shoe size. If you size up your running shoes, we recommend that you go by your casual shoe size. (See images for size chart). Although the Lycra in our products contracts when it is exposed to water and heat in the wash, it has incredible recovery properties so Feetures socks will stretch back to their original size after the wash. Washing Instructions - Machine wash cold. Hang to dry. No bleach or fabric softeners. For best results, wash socks inside out.