I purchased this myself as a used item, so it shows signs of use. Inner cup diameter: 33.0 mm Outer cup diameter: 47.7 mm Throat: 8.2 mm (※Quoted from an overseas website) There are fine scratches, but they do not affect performance. It gives the impression that it takes in a lot of air and produces a solid sound. I think you can get a rich sound even with large instruments, BB♭, and C tubas. Since there is no case, I will ship it in a separate mouthpiece pouch. I will wash it again before shipping.