These two Robert Tucci tuba mouthpieces are made with a larger shank for use with Kaiser tubas with an XL receiver. Rudolf Meinl, Alexander 164, some larger Gronitz and Hirsbrunner models are a few of the tubas that use this shank.
These mouthpieces are made with a medium weight shell for more clarity and faster response.
RT-50L: Middleweight Champion - for most tubas
RT-88L: Light Heavyweight Champion - for largest tubas