Tenor/bass valve trombone. Nominal pitch: (C+G)/(B?+F).

Technical description: Brass, long model. Tuning-slide in distal bow. With extension piece fitting between body and tuning-slide. Extension piece differs a little from instrument in details of design and workmanship, suggesting that it was not part of the original but was added only slightly later. No tuning-slide in bell section. Wide loop at end of 4th v.t.s. Wired bell rim, no garland. Fitting for music card-holder on mouthpipe. With water-key on distal bow. R1: 2 semitones. R2: 1 semitone, R3: 3 semitones, R4: perfect fourth. Valve type: Four 'Système Belge' double-piston valves, in line.