2x Pack of 4 20mm outside radius x 12.5mm inner radius x 5mm thick 90 degree curvature Each magnet's north and south pole are on opposite flat faces Four of these are required to create a full circle Each magnet can support 5kg pull vertically from the magnetic face when in flush contact with a mild steel surface of equal thickness Each magnet is coated with three layers of nickel, copper and nickel to give superior corrosion resistance and provide a smooth and clean finish
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