Shaft Collar System of Measurement Metric with Inch Bore Bore Type Round Bore Diameter 7/8 in Bore Thread Size Not Applicable Collar Outside Diameter 42 mm Inside Height to Flat Not Applicable Clearance Diameter 49.5 mm Collar Width 15 mm Collar Material Stainless Steel Keyway Width Not Applicable Collar Material Grade 303 Keyway Depth Not Applicable Thread Direction Not Applicable Center to Lever Top Not Applicable Collar Construction 2-Piece Screw Material Stainless Steel