It appears the shank has been shaved down. I don't know much beyond that, as it's not mine, so please understand. PT-84 (B/C) Cup Characteristics: Diameter 32.0mm, hemispherical and deep. Rim Characteristics: Width 8.0mm, both the inner and outer rims are quite rounded. Throat Bore: Diameter 8.0mm This is a best-selling mouthpiece by Perantucci. It's a German-style U-cup mouthpiece, but it also offers high flexibility, making it suitable for a wide range of players, from beginners to advanced. It's one of the recommended mouthpieces for those who are new to the tuba.