This is a set of axle bars that will upgrade the factory axles to be able to handle 500HP. 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 center bars that will fit your stock inner and outer CV. This kit comes with both axle bars, boots, clamps and grease. Also available are the Level 2.9 complete axles and a Level 5 1000HP set.