This is a set of the Trumpet Mouthpiece "Commercial 10-1/2MV" and a neoprene mouthpiece pouch. It is designed to take advantage of the comfortable feeling of the Bach Standard model and the good projection of the Bach Megatone. It has a standard #27 (.144") throat and a flat rim that has been modified for comfort for the commercial model. Diameter 15.34mm Cup depth Modified-V Neoprene pouch for brass mouthpieces. The lightweight and stretchy material fits the mouthpiece perfectly. The durable cushion means you don't have to worry about damaging your instrument even when it's stored in an instrument case.
