Key of Bb. Features a .484" bore, 8" hand-hammered bell, Monel pistons, nylon valve guides, and lacquer finish. Offering a solid, centered tone and excellent response, the TR690 is a doubling instrument with fingering as a trumpet or baritone. Beautifully suited for jazz and concert band work. An excellent choice for the baritone player who plays in a jazz band. Includes mouthpiece and a deluxe wood shell case.