Strong magnets with a hole are called ring magnets. A distinction is made between neodymium ring magnets and ferrite ring magnets, whose characteristics are different. Neodymium ring magnets are considered to be the strongest magnets in the world and, in direct comparison, have a higher magnetic strength at a smaller size than ferrite ring magnets. In turn, ceramic ring magnets are more temperature resistant and can be exposed to very high temperatures up to 200°C.