The Sup Calf leash provides protection to keep you attached to your board while providing a quick means of recovery. Dakine relies on its longtime heritage as a surfboard leash brand founded in 1979 in the production of the Sup Calf Leash. This high quality 5/16-inch Dura-Cord leash is intended for up to double overhead surf with Easy Clip compatibility. Additional features include a 1.5-inch molded neoprene calf cuff, marine grade stainless steel swivels and durable Opti-Flex leash ends. 12' x 5/16'' (3.66m x 8mm). Material: Urethane, Stainless Steel.