Full floating stainless steel 220mm brake rotor with aluminum carrier to fit most pit bikes and miniGP bikes. 76mm center hole diameter with 100mm bolt spacing. These discs run the floating rivets real close to the hub and could interfere on some models. Alternate mounting holes can be drilled, or hub can be scalloped to clear. The rivets are tight when new and may cause the rotor to run with a slight wobble until worked in. Once a few heat cycles have gone through the unit they loosen up nicely.