Bach Mouthpiece Extensions and Adaptors Trumpet Mouthpiece Extension Bach mouthpiece extensions allow the player to tweak the tuning of the instrument a bit by moving the mouthpiece further out in the receiver Available for trumpet and tenor trombone Mouthpiece adaptors allow cornet mouthpieces to be used on trumpets; French horn mouthpieces on Mellophones; tenor trombone mouthpieces on bass trombones; and tenor trombone mouthpieces on European euphoniums (medium shank) This allows the player to stay on the same mouthpiece when changing horns Bach Mouthpiece Adapters and Mouthpiece Extensions allow the player to use their favorite mouthpiece on other instruments that may not be built for that particular mouthpiece