Hammond Design Bass Trombone Mouthpiece - Large Shank 21BXL Silver Plated (SP) Cup Inner Diameter: 29mm Similar to: Schilke 60 Cup BXL: Deep, bowl-shaped cup ★This mouthpiece was purchased new and only test-played a few times. There are some minor scuffs from use, but no noticeable scratches, and it looks almost new. Custom mouthpiece designed and crafted by Carl Hammond, who worked as a mouthpiece craftsman for the Schilke company. The BXL is larger in volume than the BL type (standard depth V-cup) and is the largest size in the series. Popular among players who prefer larger sizes, it offers a wide and open blowing experience and doesn't break down even at high volumes.