Although he temporarily retired from instrument making in 2002, this is a Jerome Callet mouthpiece with a new design announced in June 2007. The Super Chops series mouthpieces were developed based on a 1940s Calicchio handmade mouthpiece that Jerome Callet accidentally discovered. The inner rim diameter is slightly larger than a Bach 10-1/2C. The rim is flat and quite thick. The cup has a shallow double-cup shape, shallower than a Bach F. The throat area just before the bore is slightly thicker, with a double-cup shape like a Paduba. The throat is a #29. The backbore is similar to a Warburton 6. Although it's a small size, it doesn't feel light; it has a dense, brilliant, and rich sound. It's designed for easy high notes. It's a very efficient and responsive mouthpiece. Please feel free to ask if you have any questions.