This listing is for 6 round base magnets consisting of a strong grade 8 ceramic magnet encased in a chrome plated steel cap that measures 5 cm across that magnifies the strength of the magnet by routing the north and south poles of the magnetic fields along the cap which gives this product a pull force of 15.9 Kilograms. There is also a hole in the cap that is meant for a #8 screw that allows for completely flush installation of this cup magnet which further prolongs the life of the magnet by removing any high points of contact. This product is great for use in environments in which neodymium magnets are either not suitable or even too strong.