Provides torque transmission and alignment Cost effective coupling design Easily installed where major disassembly would otherwise be required Black oxide provides some corrosion resistance 'Rigid Shaft Coupling, One Piece Clamp Type, With Keyway, Bore Dia. 5/8 In., Overall Length 1-1/4 In., Outside Dia. 1-1/4 In., Clearance Dia. (In.) 1-1/4, Screw Size (In.) 5/16-18 x 5/16, Keyway Width (In.) 3/16, Max. Torque (In.-Lbs.) 469, Max. RPM 1800, Steel Material'