Monette Prana STC B3 S3 Trumpet Mouthpiece

From Monette:

The B3S3 rim and cup size compares to the common 1 1/2C, and is a great fit for people who love that size and do not wish to play a larger rim diameter. The B3S3 rim contour has a bit more bite on the inside edge (compared to a Monette B2S3 or B4S S2), and the rim feels a little bit narrower on the chops. It is most often used by classical and orchestral players, and is great for all-around playing.