This replacement dual ball for the Rebellion XD ball mount is designed to mount onto the vertical shank. It has a 2" ball rated for 10,000 lbs. and a 2-5/16" ball rated for 15,000 lbs. The Rebellion XD adjustable ball mount is a leap forward in cushion hitch technology. It provides more control, confidence and a more comfortable ride, all while protecting your towing system from jerking, jarring and rattling. The Rebellion XD is not included in this package and must be purchased separately.