Griego CS1 For Bass Trombone Large Bore Silver Plated SP Rim Diameter: 27.99mm Throat: 7.92mm ★This item was purchased used and has been test-played a few times. There is some minor wear, but the exterior has no major dents. This is a model that comes with Getzen bass trombones. It is treated as an accessory in Japan, but is normally sold by Getzen overseas. It is compact and easy to handle for beginners and junior high/high school students.