The new MASTERS mouthpieces feature a specific bore, a new chamber as well as a new exterior design. ,Three models have been developed with facings specific to this series: CL4, CL5 and CL6. They are very easy blowing and have exceptional sound and tuning characteristics. ,,They can only be used with MASTERS series M/O metal ligature or with flexible ligatures, like Leather or Klassik Vandoren ligatures. ,,CL4 : the CL4 is characterized by a very radiant, clear sound and exceptional intonation. It allows precise, easy blowing and flowless articulation. ,,CL5 : the CL5 is characterized by a round, full sound, exceptional intonation, and perfect homogeneity and projection. ,,CL6 : it has the same sound aesthetics as the CL5, with increased ease of blowing and projection.