Willie's Bottom's Bells N-T5 L χ This model is supervised by Naoto Ohba, principal trombone player of the Tokyo Symphony Orchestra. Inner rim diameter: 25.8mm Throat diameter: 7.2mm 5M...Medium weight 5L...Light weight A full-fledged orchestra mouthpiece has arrived. With its velvety, delicate sound and outstanding ease of playing, it fits well with any instrument. 【New material "χ-metal" (Kai Metal)】 A more dense sound with a more agile response. It's easy to play and sounds great, a highly acclaimed new material. Retail price: 49,500 yen