100% Neoprene boots ensure excellent ozone resistance, which eliminates cracking, a leading cause of boot failure. High quality grease withstands high-temperature and pressure extremes, which extends joint life. Splines are chased 100% to ensure proper fit of axle into the mating hub and transmission, which eliminates installation hassles. Threads are chased 100% to ensure proper fit when axle nut is installed. High-tech grinding machines maintain the original design of the outer housing, race and cage to guarantee reliable performance. Boot clamps are pneumatically crimped creating a perfect seal between the boot and housing.