This RBC Spherical Plain Bearing 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. Designed to support heavy unidirectional thrust and combination radial/thrust loads, this bearing utilizes elliptical lubricating grooves to allow grease to get to the load zone. The spherical contact surfaces are precision ground to maximize surface-to-surface contact of inner and outer rings. 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.