They are an alloy of Neodymium, Iron and Boron (NdFeB).
This item is one of the most versatile and useful that we sell. It is a hook that has a permanently attached super powerful neodymium magnet on the base.

There are various factors which will impact how much this hook will hold in your application. Some of the factors include the thickness of the metal that you are attaching to, the iron content of the metal, thickness of the paint or other covering and on lateral loads how smooth the surface is. Always test to ensure that the weight is not too great for the hook so that whatever your are holding doesn't fall down.

Here are just some of the uses I have seen my customers use them for: Lightweight coat hook, key hook, holding banners and signs, holding products to market stands, holding pots pans and utensils, drop lights, and all sorts of other things. They will stick to lockers, fridges, filling cabinets, notice boards, or any surface a magnet will stick to.