Shaft Coupler Body Coupling Size FC25 Outside Diameter 2 1/2 in Coupling Overall Length 4 1/8 in System of Measurement Inch Hub Material Carbon Steel Maximum Speed 3 450 RPM Keyway Depth 1/8 in Keyway Width 1/4 in Bore Diameter 1 3/16 in Shaft Locking Type Set Screw Bore Type Round Bore with Keyway Jaw Profile Straight Bore Tolerance +0.001/-0.000 in Hub Diameter 2 1/4 in