Shaft Collar, System of Measurement Inch, Bore Type Round, Bore Diameter 1/2 in, Bore Thread Size Not Applicable, Collar Outside Diameter 1 1/2 in, Inside Height to Flat Not Applicable, Clearance Diameter Not Applicable, Collar Width 13/32 in, Collar Material Aluminum, Keyway Width Not Applicable, Collar Material Grade 6061, Keyway Depth Not Applicable, Thread Direction Not Applicable, Center to Lever Top 0.75 in, Collar Construction 1-Piece, Screw Material Stainless Steel This product contains a chemical that is regulated under California Proposition 65. Warning: This product contains a chemical known to the State of California to cause cancer. Warning: This product contains a chemical known to the State of California to cause birth defects or other reproductive harm. -