I'm no mouthpiece expert, but one day several months ago I went to some music store and tried out some mouthpieces. One was a Bobby Shew mouthpiece, not the "lead" kind. I'm not sure how many kinds of Bobby Shew mps there are, but here are the notes I put:
Shew 1.5 (assuming I read my notes correctly on this one)
Basically, I'm trying to find out what exactly the kind of Bobby Shew mp this is, and how it converts to sizes on other brands. Of course I cannot convert it until I find out what mp this is. I hope these notes are enough. Thanks.