Description: This is special designed for balance wheels with or without a center hole, or for a hole that is out of round, or center holes that do not fit the mounting cones, or mounting cones has been damaged, or mounting cones is not accurate. It Is a great design and quality made, easy to use, and balance more accuracy, it is good for using in the garages, tyre wheel business, mechanic workshop etc. Wheel balancers come with a standard set of mounting cones which allow the operator to mount wheels that have a "true center". but If your business is geared toward the high performance market, then this adapter is the perfect option for your wheel balancer. Can balancer those custom wheels that require a special mounting procedure, and wheels that have either a closed center or wheels that are made "without a true center" and classified as lug-centri Can be used with most of cars, vans and light trucks with closed center wheels or lug-centric wheels (wheels which do not have true center or do not rely on the hub for centering). Size adjustment method: you can adjust it yourself (if you want a 36mm hole, install the 36mm center of gravity ring. If you want a 38mm hole, install the 38mm center ring. If you want a 40mm hole, do not install the 36mm center ring and the 38mm center ring) The package includes: 1 x balance machine universal fixture