DID is the OEM of many Japanese and European brands. Leading racing teams in the Road and off-road sports rely on the technology of DID. DID 525VX: The development of the 525VX is based on the long - term experience of DID in the MotoGP and Fulfills the highest demands through the use of the patented X-rings. Compared to the O-ring equipped V-series, the 525VX has a higher strength and A higher wear resistance. - high durability and low friction due to patented X-ring Gold-colored outer pockets, black inner pockets (G & B Gold and Black).