Shaft Collar System of Measurement Inch Bore Type Round Bore Diameter 1 1/2 in Bore Thread Size Not Applicable Collar Outside Diameter 1 in Inside Height to Flat Not Applicable Collar Width 7/16 in Collar Material Alloy Steel Collar Construction 1-Piece Screw Material Steel Bore Tolerance +0.001/+0.003 in Collar Material Finish Zinc Plated Screw Thread Size 1/2 In.-13