Shaft Collar System of Measurement Inch Bore Type Round Keyed Bore Diameter 1 in Bore Thread Size Not Applicable Collar Outside Diameter 1 3/4 in Inside Height to Flat Not Applicable Clearance Diameter 2.03 in Collar Width 1/2 in Collar Material Aluminum Keyway Width 1/4 in Collar Material Grade 2024 Keyway Depth 1/8 in Thread Direction Not Applicable Center to Lever Top Not Applicable Collar Construction 2-Piece Screw Material Alloy Steel Screw Material Finish Black Oxide