Babbitt metal

Babbitt metal is a metal that has very little friction. It is used for bearings. It can be made from tin, copper, antimony, or lead. Normally it is a certain mixture of these metals. It is very soft. There are harder and softer parts in it, though. This creates small holes where grease can go in when the soft parts rub away. An item with bearings could be a fidget spinner or a bicycle wheel.