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.
An added bonus is that this set can be used on the center tenon of most clarinets as well. Using an inside and outside tuning reing here will help stabilize the joints.
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!