Original E. Schmid 14 Horn Mouthpiece Inner rim: ferric gold plating. Acoustic treatment by GAT Custom Brass. When I purchased it, the previous owner told me it had been acoustically treated (with or without engraving as an option), although there is no GAT treatment engraving. Rim inner diameter: 18.5mm Throat diameter: 4.3mm Cup depth: medium There are some scratches on the shank from use, but other than that, I subjectively think it's in good condition.