This is the Rear Bearing for the following engines: -21 EX-M ABC -21 RX-M ABC -21 EX-R ABC -21 RX-R ABC -21 EX-B ABC -21 RX-B ABC INCLUDES: One Rear Bearing SPECS: Inner Diameter: 13mm Outer Diameter: 24mm Thickness: 6mm Bearing Markings & details: Japan IJK 6901 has a plastic raceOS EnginesPart OSM23930000