Trombone Two Pack | Bass Trombone & Valve Trombone Bundle Band Director Recommended Trombone Pack - 2 Trombones Included - Bass Trombone and a Valve Trombone The Band Directors Recommended Bass Trombone is an extremely responsive horn with outstanding resonance and projection. The Trombone comes complete with a custom case and mouthpiece. This is an excellent choice for any advancing player. Bass Trombone features a lacquer finish, a red copper bell.-Double rotor.-Bore: 0.56''.-Bell: 9.5''. Includes custom deluxe case and mouthpiece. The Valve Trombone features a lacquer finish, Stainless steel valves. Bore: 0.5''.-Bell: 7.88''. Includes: custom case and mouthpiece.