The Masters Bb Clarinet Mouthpiece features a chamber unlike any other Vandoren has designed before. The outer shape of the mouthpiece is conical, which provides more room for the redesigned chamber. A new tip opening and facings offer easy playability across a wide range of reed strengths. The resulting sound will make you a believer. The Masters Bb mouthpiece comes in three facings: CL4, CL5 and CL6, and requires its own specially designed M|O ligature.