The hard chrome plating forms a tough, low-friction layer on the rod’s surface, protecting against abrasion, scratching, and surface fatigue. With a chrome plating thickness between 10 and 30 microns and a minimum hardness of 800 HV, these rods maintain their shape and function even after long periods of use. https://www.wuxixinluoyy.com/ck45-steel-piston-rod.html