Instant purchase available ⚪︎ Model Number: ZH1A Silver Plated Inner Diameter: 17.5mm Throat Diameter: 0.158 inch → 4.0132mm Cup: Deep Shank: American This is a mouthpiece from Ultimate Brass, a signature model of Mr. Yun Zeng, principal trumpet of the Berlin Philharmonic Orchestra. (The specifications are listed on the Ultimate Brass HP, but the throat diameter is calculated by multiplying the inch value by 25.4) I purchased it about 6 months ago for 22,000 yen. There are scratches on the shank from attaching it to the instrument.