Old but new unused Rudy Muck 19C Cushion Rim Cornet MouthpieceUnopened in original black, leatherette purse.Made in EnglandI don't know very much about these mouthpieces apart what is engraved on them and printed on the purse. The comments below that I received will be a better guide for you. "It's primarily for a Schilke Eb Soprano Cornet. It didn't quite fit the receiver - slightly too small. but with a piece of clear tape wrapped around the shank it fitted ok, so I'm happy with it. I have another soprano cornet - John Packer - and it fitted that without any tape." H. Another piece of advice received:"... the cornet MP is for a suprano cornet, not a normal cornet so will not fit. However, it fits my post horn, so not all is lost." K.