These tuning rings can be glued to the mouthpiece shoulder and the mouthpiece tenon to elongate the mouthpiece by 0.75mm. Adding to the mouthpiece length has a greater affect on pitch than playing a longer barrel and is a very cost effective way of adjusting a mouthpiece to play lower in pitch. One black finished brass outer ring and one brass tenon ring
Why use a mouthpiece tuning ring?
Generally, we use a longer barrel to adjust pitch when a specific mouthpiece and clarinet combination is too high in pitch. Using tuning rings is beneficial in two significant ways. You may have a barrel that you LOVE and just do not want to switch to another - a tuning ring added to the mouthpiece negates that problem. And, this adjustment is much less expensive that buying a new barrel!