This is a silver-plated LASKEY "59E" euphonium/trombone large shank mouthpiece made by the American mouthpiece maker LASKEY. Inner rim diameter: 25.9mm Cup depth: DEEP Throat diameter: 7.11mm This mouthpiece is made by Mr. Laskey, who became independent after making mouthpieces for the Silky company. The one offered here is a re-edition made after his passing. I believe this mouthpiece has a deep cup and a not-so-wide throat, making it easy to control and producing a warm sound. There are some scratches from use, but it's in pretty good condition! Feel free to ask any questions in the comments.