All brass instruments are folded or coiled tubes. They are made from metal with a lacquer finish to protect the metal, and keep them bright and shiny. They also can be silver-plated. Horns, trumpets and tubas have valves and the trombone uses a slide action. Brass instruments are wind instruments and have a cup or funnel-shaped mouthpiece. Trumpets, trombones and tubas use the cup-shaped mouthpiece and the French horns use the funnel-shaped mouthpiece.