This is a custom-made mouthpiece from HMG in Osaka. It's made of solid brass (no plating), with an inner diameter of 17.6mm, a medium cup depth, and a rim that's a hybrid of Laskey and Paxman specifications. I've used it a few times, and I think it's well-suited for classical pieces. It undoubtedly produces a beautiful sound. Horn Mouthpiece Brass, Solid Thank you for looking.