Product Details: Equip your semi to be Ready for the Road Ahead™, with the Hendrickson 415 mm Rotor Service Kit, a crucial kit to improve brake performance. By restoring the rotor to its original condition, this repair kit is able to harmonize the union of the caliper, brake pads, and rotor to actuate the brakes. Fashioned with precise standards to return the air brakes to their original working condition.