I was having a bit of a tidy up in the trumpet room the other day. I was sifting through my mouthpiece collection (I have just over two hundred!) and I came across these three old beauties. They are very similar but all have different shanks. One has the very famous Kosikup name stamped clearly but I’m hard pushed to name the other two. The middle one has no discernible markings at all but the one on the left has Prototype and the letter C.