Diff outdrives for XRAY Active Diff™ of self-developed, world-renowned HUDY Spring Steel™ – the toughest steel material available – are CNC-machined on precision German long-turn machines. The diff outdrives are additionally ground and strategically lightened to reduce rotating weight. The diff outdrives are then further hardened to ensure maximum strength and longest lifespan. The diff outdrive shafts are additionally precision hand-ground to a very high tolerance to ensure an ultra-smooth tight fit in the diff body and diff gear. Set of 2.