Features 【Can improve efficiency】Small frictional resistance, low power consumption, high mechanical efficiency. 【Wear small】This ball thrust bearing set features high precision, high speed, and wear small. 【Smooth to use】High grade steel ball, quiet and smooth rotation at a high speed. 【internal stability】Small internal clearance and high machining precision. 【Wide use】Suitable for machinery manufacturing, equipment installation and maintenance. Specification:Item Type: Thrust BearingBearing Material: Bearing SteelOptional Models & Sizes: F2.5-6M, F3-8M, F4-9M, F4-10M  F2.5-6M:Inner Wheel Inner Diameter: Approx. Approx. 2.5mm / 0.1inInner Wheel Outer Diameter: Approx. 6mm / 0.2inOuter Wheel Outer Diameter: Approx. 6mm / 0.2inOuter Wheel Inner Diameter: Approx. 2.7mm / 0.1inF3-8M:Inner Wheel Inner Diameter: Approx. 3mm / 0.1inInner Wheel Outer Diameter: Approx. 3.5mm / 0.1inOuter Wheel Outer Diameter: Approx. 8mm / 0.3inOuter Wheel Inner Diameter: Approx. 3.2mm / 0.1inF4-9M:Inner Wheel Inner Diameter: Approx. 4mm / 0.2inInner Wheel Outer Diameter: Approx. 8.8mm / 0.3inOuter Wheel Outer Diameter: Approx. 9mm / 0.4inOuter Wheel Inner Diameter: Approx. 4.2mm / 0.2inF4-10M:Inner Wheel Inner Diameter: Approx. 4mm / 0.2inInner Wheel Outer Diameter: Approx. 9.8mm / 0.4inOuter Wheel Outer Diameter: Approx. 10mm / 0.4inOuter Wheel Inner Diameter: Approx. 4.2mm / 0.2in 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. Package List