Sousaphone. Nominal pitch: E♭.

https://images.is.ed.ac.uk/luna/servlet/iiif/UoEart~2~2~40266~104538/full/,150/0/default.jpghttps://images.is.ed.ac.uk/luna/servlet/iiif/UoEart~2~2~81262~181982/full/,150/0/default.jpg