Alto trombone Model: AT 10LL Key: Bb Bell Material: Yellow Brass, Red Brass Slide Pipe Material: Yellow Brass Bell Diameter Alto tromboneModel: AT 10LLKey: BbBell Material: Yellow Brass, Red BrassSlide Pipe Material: Yellow BrassBell Diameter: 200 mmBore Diameter: 14.2 mm Finish: Gold lacquer Packing: Hardshell Plush Lined Hard Case with a pair of White Gloves Trombones