This RBC Spherical Plain Bearing Inner Race is manufactured from through-hardened 52100 bearing quality steel per ASTM A485, and heat treated to increase hardness to HRc 57 minimum for optimum wear resistance. This bearing, used in conjunction with an SA-style outer ring, is designed to support heavy unidirectional thrust and combination radial/thrust loads and can be used to replace a broken inner ring without the cost of replacing the entire bearing. This bearing is phosphate treated prior to coating with a dry film lubricant for corrosion resistance. RBC Bearings has been providing bearing solutions to our customers since 1919. A publicly-traded company (NASDAQ: ROLL), RBC currently has 23 manufacturing facilities worldwide, with 18 located in the USA.