High strength 4340 Chromoly Axle Kit designed for 1987-2006 Jeep XJ / YJ Dana 30 front axles with factory disconnect. The 50% strength increase is derived from the upgrade to 4340 chromoly, much stronger than the factory material. Furthermore, the shafts are dual heat treated, resulting in the best balance of strength and ductility. Fully assembled with heat treated full circle clips - ready to install Full Kit - LH and RH assemblies with Spicer U-Joints High Strength 4340 Chromoly Dual Heat Treated for strength and ductility Uses large 5-760X Series Spicer U-Joint Comes with block off plate when eliminating vacuum assembly, and special seal. Replaces stock with no modifications needed 15-Year Warranty!