Shaft Collar System of Measurement Inch Bore Type Round Bore Diameter 2 15/16 in Bore Thread Size Not Applicable Collar Outside Diameter 4 1/4 in Inside Height to Flat Not Applicable Clearance Diameter 4.56 in Collar Width 7/8 in Collar Material Carbon Steel Keyway Width Not Applicable Collar Material Grade 1211 Keyway Depth Not Applicable Thread Direction Not Applicable Center to Lever Top Not Applicable Collar Construction 1-Piece Screw Material Carbon Steel