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 Horsepower @ 100 RPM 2.9 hp Keyway Depth 3/32 in Keyway Width 3/16 in Bore Diameter 3/4 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