This is a ceramic front engine bearing from TKO for the O.S. MAX .21 RG, VZ-B, VZ-B V-Spec, and V-Spec 2 engines. This bearing will also fit any other .21 competition buggy engine that uses the same bearing dimensions, such as the RB Concepts and Novarossi. The bearing dimensions are 7mm inner, 19mm outer and 6mm thick.This bearing also fits the New EB Mods JS Racing engine as well