Quick Clamping Shaft Collar, System of Measurement Metric, Bore Type Round, Bore Diameter 12 mm, Bore Thread Size Not Applicable, Collar Outside Diameter 28 mm, Inside Height to Flat Not Applicable, Collar Width 13 mm, Collar Material Plastic, Keyway Width Not Applicable, Collar Material Grade Acetal, Keyway Depth Not Applicable, Center to Lever Top 32.2 mm, Collar Construction 1-Piece, Screw Material Stainless Steel, Resistance Properties Corrosion Resistant, Screw Seating Torque 1.1 N-m