The Bach 7C trumpet mouthpiece is the most widely used model. It has a brilliant tone and is preferred by school musicians and musicians who are beginner trumpet players.
The Bach 5C trumpet mouthpiece is for players with a strong embouchure who do not like a sharp edge. The tone is rich and lively.
The Bach 5B trumpet mouthpiece has a precise rim and a fairly large cup. The tone is full and vivid.
The Bach 3D trumpet mouthpiece is fairly large and has a medium shallow cup the produces a more brilliant tone. The mouthpiece facilitates, or makes easier, playing in the high register.
The Bach 3C trumpet mouthpiece has a fairly large cup and is good for all-around use.