YAMAHA Cornet Mouthpiece, Excellent Condition Rim Diameter: 16.44 Cup: DEEP Throat: 4.50 Thank you for viewing. This is a rare, vintage YAMAHA mouthpiece. It came with a used, excellent condition custom series cornet (NEO grade if it were a current model), which I recently purchased. The size is too small for me, so I'm hoping someone will use it. It's in great condition, as shown in the pictures. There are few shank marks, and no scratches on the rim.