This is a set of axle bars that will upgrade the factory axles to be able to handle 550HP. The factory CV's are made from Japanese spec material very close to our 4130 chromoly, but the center bars are made from a brittle lower grade material. What we have made is a custom set of aerospace grade torsional center bars that will fit your stock inner and outer CV. This kit includes both axle bars, boots, clamps and grease.