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Shaft Collar, System of Measurement Inch, Bore Type Round, Bore Diameter 3/8 in, Bore Thread Size Not Applicable, Collar Outside Diameter 3/4 in, Inside Height to Flat Not Applicable, Clearance Diameter 0.75 in, Collar Width 3/8 in, Collar Material Carbon Steel, Keyway Width Not Applicable, Collar Material Grade 1211, Keyway Depth Not Applicable, Thread Direction Not Applicable, Center to Lever Top Not Applicable, Collar Construction 1-Piece, Screw Material Carbon Steel