Marucs Bonna Case for Detachable Bell Bass Trombone - Black NylonThis model fits a bass trombone with a detachable bell with or without rotary valves. The bell, with a maximum size of 10. 5 inches, is stowed under a foam bell protector. The instrument's body is fixed by a velcro belt and the slide is secured to the lid. There is space for accessories in a compartment inside or in the exterior detachable sheet music bag. The case includes: 2 backpack straps 1 shoulder strap 1 mouthpiece pouch for three mouthpieces 1