Shaft Collar System of Measurement Inch Bore Type Threaded Bore Diameter 3/16 in Bore Thread Size #10 -24 Collar Outside Diameter 5/8 in Inside Height to Flat Not Applicable Clearance Diameter 0.77 in Collar Width 9/32 in Collar Material Carbon Steel Keyway Width Not Applicable Collar Material Grade 1215 Keyway Depth Not Applicable Thread Direction Right Hand Thread Center to Lever Top Not Applicable Collar Construction 1-Piece Screw Material Alloy Steel