Keyed Shaft Collar, System of Measurement Metric, Bore Type Round Keyed, Bore Diameter 25 mm, Bore Thread Size Not Applicable, Collar Outside Diameter 45 mm, Inside Height to Flat Not Applicable, Clearance Diameter 52.1 mm, Collar Width 15 mm, Collar Material Carbon Steel, Keyway Width 8 mm, Collar Material Grade 1215, Keyway Depth 3.5 mm, Thread Direction Not Applicable, Center to Lever Top Not Applicable, Collar Construction 2-Piece, Screw Material Alloy Steel WARNING: This product can expose you to chemicals including Ethylene thiourea, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov. -