This is an old model Breslmair mouthpiece. The model number is the same as the current one. 3 Rim: Wide and round, 4.07mm F Inner Diameter: 17.60mm 4 Cup Depth: Deep S Backbore: German style, for French horn I believe this is the model closest to the mouthpiece widely and generally used in Japan among Breslmair mouthpieces. The shank has been shortened to fit the 5000 series Alexander I used previously, so it probably won't fit American shanks. Depending on the age, it might be loose in European shank instruments as well. I liked the tone, responsiveness, and beautiful appearance, and I used it for a long time. There are no noticeable scratches that would affect playing, but I have marked the condition as "poor" because it has been adjusted and some people may be concerned about the stress on the mouthpiece.