attwood 11216-1 Trailer Boat Heavy-Duty Rubber 10" x 5/8" Shaft Keel Roller, Black Non-marring, durable rubber protects your boat's finish Molded rubber over steel tube with nylon end inserts Extremely tough, designed specifically for heavier boats Inward taper and "v"-cut eases handling of larger vessels Attwood develops high value, engineered marine products that are tested on-site in our lab to make life on the water easier to enjoy