DID is an OEM of many Japanese and European brands. Leading racing teams in the Road and off-road sports rely on the technology of DID. DID 520VT2: The 520VT2 is a particularly narrow X-ring chain for use in Enduro Racing. Due to the narrow design, it can often also be used with Enduro Racing models, which have narrow space conditions and are equipped with chains without a sealing ring on the manufacturer's side. The low friction of the patented X-rings also reduces the power loss in the drive train and is a guarantee of high wear resistance. - high wear resistance thanks to patented X-ring technology -male construction Gold-colored outer pockets, black inner pockets (G & B Gold and Black).