Bach Trombone Mouthpiece for Tenor Trombone - Small Shank VINCENT BACH CORP. 12C Inner Rim Diameter: 24.50mm Cup Depth: M With Box In my personal opinion, this is a "deep period" Bach mouthpiece, likely manufactured in the 1970s, as indicated by the wide spacing between "CORP." and "12C" on the engraving. There are scratches on the shank from attaching and detaching the instrument. There is a dent on the rim (see photo 5), but I don't think it will affect your lips when playing. Considering its age, the appearance is quite good, but please understand that this is a used item before purchasing. ⭐︎Please also read the profile.