Shaft Coupler Body Coupling Size L150 Outside Diameter 3 3/4 in Coupling Overall Length 4 1/2 in System of Measurement Inch Hub Material Carbon Steel Maximum Speed 5 000 RPM Horsepower @ 100 RPM 2 hp (Buna-N Spider) 5.88 hp (Hytrel Spider) Keyway Depth 5/32 in Keyway Width 5/16 in Bore Diameter 1 3/8 in Shaft Locking Type Set Screw Bore Type Round Bore with Keyway Jaw Profile Straight Screw Thread Size 3/8-16 UNC Hub Diameter 3 3/4 in Hub Material Grade 1045