https://www.instructables.com/Silicone-Rubber-Tootophone-Mouthpiece/
Silicone Rubber Tootophone Mouthpiece : 3 Steps (with Pictures) - Instructables
Silicone Rubber Tootophone Mouthpiece: The sound produced by my tootophones has always been a bit tinny, and difficult to combine with traditional instrument...
silicone rubberwith picturesmouthpiecestepsinstructables