Bruno Tilz French Horn Mouthpiece, McWilliam Model, #1. Shank: American Shank Inner Rim Diameter: 17.5mm Throat Diameter: 4.4mm Cup: Medium depth Although the cup is described as medium depth, it feels quite deep when actually played. It has been used, so there is some plating wear, discoloration, and scratches. Also, the tip of the shank on this model is thin, so it is prone to distortion. There are no major dents, but it is uneven. (I think a repair shop can fix it for a few hundred yen.)