Rigid Shaft Coupling, 1 Piece Clamp, Inch, Bore Dia. 2 in, Steel, Finish Black Oxide, Outside Dia. 3 9/16 in, Overall Length 3 9/16 in, Without Keyway, Clearance Dia. 3.563 in, Screw Size 3/8 In.-24, Max. Torque 13,680 in-lb, Max. RPM 4,000 RPM