Motion Control Coupling Hub, Angular Misalignment 0.5 Degrees , Axial Motion 0.004 in, Coupling Size OST12, Outside Diameter 0.75 in, Over-Standard Parallel Misalignment 0.075 in, Parallel Misalignment 0.008 in, Coupling Overall Length 0.875 in, Hub Material Aluminum, Length through Bore 0.3 in, System of Measurement Inch, Bore Diameter 1/4 in, Maximum Speed 4,500 RPM, Bore Type Round, Shaft Locking Type Set Screw, Keyway Depth Not Applicable, Keyway Width Not Applicable