These 13mm (0.51") circular disc magnets are coated in red and green plastic. They are red on one side, and green on the other so that they can be used for stock allocation and management. By simply flipping the magnet over you can interchange quickly between the red and green faces. The magnets are made from N42 neodymium rare earth magnets and provide a vertical pull of 1.2kg (2.65lbs).