Shaft Collar System of Measurement Inch Bore Type Round Bore Diameter 2 5/16 in Bore Thread Size Not Applicable Collar Outside Diameter 3 3/8 in Inside Height to Flat Not Applicable Clearance Diameter 3.59 in Collar Width 3/4 in Collar Material Aluminum Keyway Width Not Applicable Collar Material Grade 2024 Keyway Depth Not Applicable Thread Direction Not Applicable Center to Lever Top Not Applicable Collar Construction 2-Piece Screw Material Alloy Steel