This is a rare trombone rim, trumpet shank mouthpiece for trumpet. The following is the manufacturer's description: A trumpet mouthpiece for trombone/euphonium players, a long-awaited item. Also ideal for trumpet players' warm-up & cool-down. Rim inner diameter: 24.4mm, Throat diameter: 4.5mm *Trumpet shank There are no major scratches or dents that would interfere with playing. Please refrain from comments asking for a price reduction. Immediate purchase is OK. If you are interested in used or new mouthpieces, please search for Net Brass. www.net-brass.com