High quality replacement springs designed to exceed the OEM specifications by fitting precisely on the spring shoulder diameter of both OEM retainers, and Kibblewhite Performance Machining Inc. (KPMI®) heat treated (H.T.) steel retainersDesigned to provide pressures to control stainless steel valvesKit includes H.T. steel basewashers to ensure a precision fitment on the larger end of our beehive springManufactured in the USA