The fendergrip gives you instant fender height adjustment plus a positive lock. Uses your 3/8" or 1/2" line's strength to hold fenders of all sizes.Makes fender adjustments a breeze yet installs in seconds to cleats, grab handles, and hand rails of any shape and size. 2 fendergrios can store a fender on rails to be deployed horizontally or verticallly. Made of rugged DuPont Derlin and stainless steel hardware. Used by the U.S. Coast Guard and Marine Police Agencies. Lifetime warranty.