DID Drive Chain 525ZVM-X2 -122 ZB Super Street X-RingDID Drive Chain 525ZVM X2 122 ZB Super Street X Ring The D. I. D ZVM X Series utilizes our patented X Ring seal and has greater strength than the VX Series and is designed for heavyweight motorcycles with tremendous torque and horsepower. The twisting action of the X Ring increases its sealing performance and its four contact points minimizes power loss. The ZVM X Series Direct Energy Transfer, born from our experience in MotoGP, means greater stretch