CAR WAX! Like previously mentioned, it does work. Just apply it (use some elbow grease to take off dirt), let dry, and then wipe off. I use it on all my horns, even gold-plated. It doesn't eat away at finished and doesn't take off any of the metal. I personally use the orange "Once a Year Car Wax." I've found that it works the best. It keeps protected and shiny for quite a while.