The BULLDOG removable caster with poly wheel is an option for the trailer jack. It is designed to provide easy roll and excellent ground support, which simplifies the process of physically moving various types of trailers. It is also a genuine BULLDOG replacement part. Using genuine BULLDOG replacement parts is the best way to maintain the integrity of any BULLDOG product as it is manufactured by the most trusted name in the industry.• Compatibility: 1200 Pounds Lift Capacity Jack With 2 Inch Round Inner Tube• Diameter (IN): 6 Inch• Material: Steel• Color: Zinc• Hardware Included: Yes• Roll Pins included: Yes Easy to use snapper pin For use with 2 in. inner tube Size 9 in. W x 4 in. L x 11 in. H | Fulton Bulldog Trailer Tongue Jack Caster w/ 6 Inch Wheel & Pin/Clip, 1,200 lbs Capacity