My magnet cleaner, the one used on the outside of the tank, was worn down from use. So I went to Micheals the craft store and bought this sheet of felt for 99 cents and used it to resurface the magnet. The sheet is large enough to get about 12 cuts for the magnet out of it. And it is peel and stick. So don’t throw away your worn felt magnet, just go and replace the felt.