Features This ball thrust bearing set features high precision, high speed, and wear small. Small internal clearance and high machining precision. Suitable for machinery manufacturing, equipment installation and maintenance. Small frictional resistance, low power consumption, high mechanical efficiency. High grade steel ball, quiet and smooth rotation at a high speed. Package List: 10 x Thrust Bearing   Note: 1. Please allow slight error due to manual measurement. Thanks for your understanding. 2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard. Specification: Condition: 100% Brand New Item Type: Thrust Bearing Bearing Material: Bearing Steel Optional Models & Sizes: F9-20M, F10-18M, F12-21M F9-20M: Inner Wheel Inner Diameter: Approx. Approx. 9mm / 0.4in Inner Wheel Outer Diameter: Approx. 19.8mm / 0.78in Outer Wheel Outer Diameter: Approx. 20mm / 0.8in Outer Wheel Inner Diameter: Approx. 9.2mm / 0.36in F10-18M : Inner Wheel Inner Diameter: Approx. 10mm / 0.4in Inner Wheel Outer Diameter: Approx. 17.8mm / 0.7in Outer Wheel Outer Diameter: Approx. 18mm / 0.7in Outer Wheel Inner Diameter: Approx. 10.2mm / 0.4in F12-21M: Inner Wheel Inner Diameter: Approx. 12mm / 0.5in Inner Wheel Outer Diameter: Approx. 21mm / 0.8in Outer Wheel Outer Diameter: Approx. 21mm / 0.8in Outer Wheel Inner Diameter: Approx. 12.2mm / 0.5in Package List