Polyform U.S. NF-4 Heavy Duty Twin Eye Fender 6.4" X 21.6" - White NF-4 WHITE. The NF Series is an extra tough recreational-boating fender and a good choice for use in boat locks and tidal areas where fenders are exposed to high stress situations. The NF Series is designed to last and stand up in the toughest conditions as well as being compact for easy storage in smaller craft. Features of Polyform U.S. NF-4 Heavy Duty Twin Eye Fender 6.4" X 21.6" The NF Series blends the styling of the G Series (the world's most copied fender) and the multi-ribbed ropehold of the F Series (the strongest fender in its class). Sleek one-color styling Reinforced twin-eye ropeholds for flexibility and durability Designed for medium-duty use in both permanent protected and unprotected moorings. Unique Polyform valve for years of service. Package Contents: Polyform U.S. NF-4 Heavy Duty Twin Eye Fender 6.4in X 21.6in Polyform U.S. NF-4 WHITE: NF-4 Heavy Duty Twin Eye Fender 6.4" X 21.6" - White