Here is a new double trombone case by Marcus Bonna in Brazil. You'd think it fits a viola but it's actually made for two tenor trombones with screw bells. If you have a smaller Bb tenor jazz trombone and a larger Bb/F tenor trombone, both with screw bell flares, you can use one case to carry everything. Some of Bonna's photos show an Eb/Bb alto trombone instead of the small tenor, so it's not a restrictive case. In fact, some of the pics above are the tenor/alto case. It's nearly identical. (Don't tell anybody.)
Made of fiberglass with nylon outer cover and removable music pocket with stand straps. Includes backpack straps, shoulder straps, mouthpiece pouch and leadpipe pouch.
One available in black nylon. Approx. 8x12x34"


