Shaft Collar System of Measurement Metric Bore Type Round Bore Diameter 8 mm Bore Thread Size Not Applicable Collar Outside Diameter 30 mm Inside Height to Flat Not Applicable Clearance Diameter 32.3 mm Collar Width 8 mm 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