This is a Flute trumpet mouthpiece. I didn't notice it when I tried it out, but after using it twice, it felt small, and I haven't used it since. It's about the size of a 7C, with a shallow cup. I think it's easy to hit high notes. When I bought it, it was a model not sold in Japan! I don't know about now... It's a 3M! Rim: 16.62mm Rim Shape: Round Rim (Standard) Outer Diameter 27.26mm Cup Depth: Medium Deep Non-refundable