Mainly used for servo motors, spindle, step motor and so on.Wear resistant ,high hardness and excellent response.Super elastic torque can absorb vibration, appropriate a large torque transmission.Specification:Color: Silver ToneNet Weight: 32gMaterial: Aluminum AlloyFixed Type: ClampThread Size: M3Connection Diameter: 10mm to 10mm / 0.39 to 0.39 inchTotal Length: 25mm /0.98 inchOutside Diameter : 20mm/ 0.79 inchPackage List:2x Flexible Shaft Coupler