Surftech Coil SUP Stand Up Calf Attachment Paddleboard Leash (Black,11 feet x 1/4-Inch) Surftech Coil Leashes reduce drag by keeping your leash up on the back of your board and out of the water. Extends to a mazimum of 11'. Max-strength double swivel urethane cord. Large velcro wrap for your calf. 7mm urethane cord. Triple wrap rail saver. Precision molded fittings.