Warm waterproof design. Mid-calf height (11”). Three layers, securely bonded together throughout. Stretch-to-fit to avoid uncomfortable sags and wrinkles, even in strenuous activity. Seamless design provides the ultimate in performance and comfort without annoying ridges and pressure points. Each sock is high-pressure tested to ensure that ithas no leaks. Men's shoe sizes sm: 5-6, md: 7-9, lg: 10-11, xl: 12-13; Women's shoe sizes sm: 6-7, md: 8-10, lg: 11-up.