Backun Clarinet Bell, 6LBCVG, Cocobolo, Traditional, with Voicing Groove Backun Cocobolo Clarinet Bell For Bb / A Clarinets Traditional Style with Voicing Groove Model 6LBCVG (Diameter 26.17mm, Depth 20.08mm) The most afforable way to improve your clarinet's tone and response. Used by professionals throughout the world.