Large strong Neodymium N42 pot magnet with a stainless steel eyebolt. Magnetism is concentrated on the one face to provide the maximum holding force. 60mm diameter x 49mm from the base of the magnet to the top of the eyebolt The internal diameter of the eyebolt is 20mm and is 36mm from base collar to top Each magnet can support a steel weight of up to 139kg vertically from the magnetic face when in flush contact with a mild steel surface of equal thickness Coated with three layers of nickel, copper and nickel to reduce corrosion and provide a smooth finish Max operating temperature 80 degrees celsius. Plating Ni-Cu-Ni (Nickel). Material NdFeB. Slide resistance 27kg. Ideal for divers, these clamping magnets offer an incredible clamping force for their size combining the performance of Neodymium with the utility of an eyebolt. These Neodymium magnets are sunken in to a steel shell meaning that the north pole is on the centre of the magnetic face and the south pole is on the outer edge around it. The steel pot increases the adhesive force of the magnets giving them an incredible hold for their size. An added advantage of these magnets is that they are resistant to chipping or cracking following constant impact with a steel surface. These magnets come with a safe-handling warning; because they are so powerful they can be dangerous if not handled carefully.