I bought this tool to clean electrical contacts and battery posts. This works very well because the brush particles are non-conductive. I've also used it to remove surface rust from steel. Also works well for this as you can access small areas that steel wool or tape can't reach. The brush is made of fiberglass and the brush pieces break off during use. They can get stuck in your skin or worse, in your eyes if you're not careful. Don't use your breath to blow away any remaining debris. Use a paper towel or rag instead.