One of a kind mouthpiece backbores.
Backbore: OS
Designed for the orchestral player who desires that large/full sound that allows the player to use massive quantities of air without losing focus. Commonly used with #22-25 throats and deep cups. Pairs well with rotary trumpets. Applications - Orchestral/Symphonic playing
Backbore: CS
Very free blowing symphonic backbore. The CS is a Symphonic short-shank backbore designed to help the intonation challenges associated with many C/D/Eflat trumpets. Applications - Orchestral/Symphonic/Soloistic/Chamber playing