From marking metal to wood to sandwich bags and more, the Sharpie® permanent markers have been gliding on posters, mirrors, CDs, and virtually anything else for decades. They are also developed with an AP certified non-toxic formula - making them safer to use in the home or the workplace. Oh, and the quick-drying ink reduces the chances of smearing or smudging while the fine tip delivers clear, visible strokes and a smoother writing experience. It's a Sharpie®. Perfect.