HNA premium liners combine the strength of a forged steel outer shell with the abrasion and corrosion resistance of a high chromium iron inner sleeve. These liners feature a centrifugally cast high chrome iron sleeve which is machined and heat treated to a minimum uniform bore hardness of 62 RC. Each liner is machined to close tolerances to assure ease of installation and long liner life with the inside diameter of these premium liners honed to a mirror-like finish for smooth even wear during the life of the liner. HNA premium liners are made for superior performance under tough corrosive and abrasive conditions.