I modeled this after my Bach 7C Euphonium (Though I think its really for trombone) mouthpiece. Its the schools, so Im assuming its a pretty common/beginner size. The model isnt perfect, but I got it pretty accutate. These things are very counter-intuitive in design, but the model works great inside and out. I cant wait till I get my vapor bath stuff, then it will really feel nice. Also, being in my school marching band, it will be great for the winter as it wont actually get so cold! :D The rim is flat in the model, unlike the real thing for ease of printing. Nothing some sanding cant fix. I may upload a comparison to the origional to youtube soon. If I do Ill post it.