Shop Nilight Gooseneck Ball Extender – GNXA4085, 4Inch Offset Ball Compatible with B&W Trailer Hitches Turnoverball Heavy Duty 2-5/16 Inch Ball 20000 lbs GTW 5000 lbs VTW in high quality, support 2 year warranty. This ball extender is made from alloy steel materials with powder coated surface which can be effectively anti-corrosion and durable.