Shaft Coupler Body Coupling Size FC45 Outside Diameter 4 1/2 in Coupling Overall Length 7 3/16 in System of Measurement Inch Hub Material Carbon Steel Maximum Speed 1 750 RPM Keyway Depth 1/4 in Keyway Width 1/2 in Bore Diameter 2 in Shaft Locking Type Set Screw Bore Type Round Bore with Keyway Jaw Profile Straight Bore Tolerance +0.001/-0.000 in Hub Diameter 4 in