Use this Davis accessory to clip your fenders to rails, lifelines, side wing windows or cleats. Fender Tender II simplifies the handling and relocation of boat fenders. The "Railing Lock" firmly grasps rails from 7/8" to 1" (22 to 25mm) diameter. New "Lifeline Lock" provides added safety. Use 1/4" to 3/8" (6mm to 9mm) diameter nylon line. Made of tough, sun resistant plastic for many years of use. Helps tidy up your boat. Don`t dock without it!!!