I had Eric Anderson at Midwest Musical Imports custom design and build this mechanism for a Wolf bocal that I have. The idea was to create a key that opens a pinhole drilled in the bocal, operated by the right hand, and have the entire mechanism completely independent of the rest of the bassoon.
All posts tagged pinhole
Harmonic flagolet key for bassoon bocal (high G key)
Posted by Trent on May 27, 2011
https://tjbassoon.com/2011/05/27/harmonic-flagolet-key-for-bassoon-bocal-high-g-key/