Ground Support Products' running gear: -Fits most manufacturers specs. -GSP hub fits the pilot of its wheel within .05in., which ensures the weight of the load is carried on hte barrel of the hub and not the lugs -GSP's welded adapting plate on the hub and axle assembly provides a more secure and reliable attachment to the rear post or verticle spindle mount -GSP's 3-stage 'soft ride' 100 precent natural rubber solid tires are mounted on a 7 gauge rim