The Custom X Fin Tether is lightweight and comfortable. It is a sandwich style mini velcro closure with double neoprene padding. Insures your swim fins will not be lost if they get pulled off your feet duing a heavy set. A true bodyboarder's fin tether, lightweight, mini double velcro "sandwich style" closure with soft neoprene backing. Thin design for optimum performance and comfort. Never worry about losing a fin when wearing these fin tethers. -Comfortable lightweight neoprene padded ankle strap. -Super strong dual sandwich style velcro fastener. -Loops onto fin and has a velcro attachment to ankle.