I am selling this item to organize my belongings. The following is a quote from SMKC: This is a mouthpiece designed from scratch by SMK Craftworks for horn players, by a horn player. It is gentle on the mouth and produces a good sound. [Brand] SMK Craftworks [Model Number] SMK-750R-BR [Shape] Cup Inner Diameter: 17.5mm Throat Diameter: 4.0mm Cup Shape: U-cup Depth: Shallow Rim: Rounded Shank: 3/100mm (European) [Surface] Solid brass finish (limited quantity) The solid brass finish will change color over time.