42/64" Medium-round with a soft bite. 42 rim is functionally similar to Bach Elkhart 3C & 6C, Bach 8C, 10B, and Schilke 14 rims.
Cup: S - 0.212" proprietary cup depth Shallow bowl shaped cup
Backbore: 2 Standard backbore. More centered than a Bach #10 with excellent tone color and intonation. This backbore works well on all of our cups. It was the 2nd backbore Bob ever made.
Shank: #4 Standard - other sizes available.
Popular Uses: Lead trumpet, commercial, amplified, concert band. A popular "gateway" lead mouthpiece for players coming from 3C diameter mouthpieces. Bright, focused sound.