Bach mouthpieces have been the standard since their creation by trumpet master Vincent Bach. These mouthpieces are designed to meet every conceivable playing need and have for nearly three quarters of a century. The Bach 6 1/2AL is slighly larger than medium with a large throat and backbore for tombonists who strive foe a Teutonic tone qhality. Tecommended for euphonium players who desire a round, mellow tone of great carrying power and substantial volume. It requires physical strength to fill as well as a highly developed embouchure. Rim Shape: Medium wide, well rounded.