Shaft Collar System of Measurement Metric with Inch Bore Bore Type Round Bore Diameter 1/2 in Bore Thread Size Not Applicable Collar Outside Diameter 30 mm Inside Height to Flat Not Applicable Clearance Diameter 33.7 mm Collar Width 11 mm Collar Material Plastic Keyway Width Not Applicable Collar Material Grade Acetal Keyway Depth Not Applicable Thread Direction Not Applicable Center to Lever Top Not Applicable Collar Construction 2-Piece Screw Material Stainless Steel