Polish and Cleaner. People often ask us what we use to clean and preserve our fine vintage instruments. For decades we have been using, with great results, Dr. Duck Ax Wax. This is NOT a gimmick. It works like a dream. It is an organic cleaning, polishing, moisturizing formula for guitars, banjos and mandolins. It can be used on the entire instrument, fretboard, headstock, front, sides, back, pickguards and metal parts. It comes in a generous 4 oz. oval shaped bottle with an applicator flip top cap. It will even help prevent fret oxidation. It is U.S. made with U.S. materials out of Nevada.