Wedge 665MDV Hybrid Trumpet Mouthpiece

There is a gap in the Bach sizing between the 1.5C and 5C. The Bach 3C has an intermediate rim diameter, but a shallower cup, and the Bach 3B has a more V shaped cup.
The 665MDV is intended to fill that gap with an ID similar to a Bach 3C and a cup depth similar to a Bach 1.5C and 5C.
The 665MDV is a great choice for a player wanting a sound similar to a Bach 1.5C, but with a slightly smaller, more efficient inner diameter.

Similar to
Bach 1.5C, 5C & 7C
Monette B3
Schilke 15
Warb 4DM & 4D
Yamaha 16C4