Shaft Collar, System of Measurement Inch, Shaft Locking Type - Couplings 1 Piece Clamp, Bore Type - Collars Plain Bore, Bore Dia. 2 in, Material - Collars Black Oxide Steel, Outside Dia. 3 in, Width 11/16 in, Clearance Dia. 3.312 in, Screw Size 5/16 In. -24, Screw Material Steel, Operating Temp. Range 0 Degrees to 300 Degrees F