Bach Standard Series mouthpieces are some of the most popular mouthpieces in the world among both students and professionals. They are categorized from large to small diameters numerically, and from the deepest to the shallowest cup alphabetically. 7C* is medium wide, lowered toward the outside. Med. sharp inside edge. Well-rounded edge with a perfect grip. Probably the most widely used model in the world. Its brilliant tone is preferred by school musicians and by artists.