Clarinet. Nominal pitch: B♭.

Technical description: Very close to (4770) and very close to Pupeschi's British patent 12,108. The R1ring system is designed so that a G♯₃/E♭₅ is available with R4 free for the F₃/C₅key (avoiding slides). The 'Pupeschi' C♯₄/G♯₅ is linked to both bascule levers and the additional L4 lever for F₃/C₅. Additional R1 side trill. Csharp mechanism. 15keys, 6rings, 1covered tone-hole, 4black rollers. L0: T + ring; speaker. L1: T + ring + vent; throat A♮; throat A♭. L2: T + ring + vent. L3: T; E♭₄/B♭₅. L4: C♯₄/G♯₅; E₃/B♮₄; F♯₃/C♯₅; alternative lever for F₃/C₅. R1: Plate + ring + vent articulated alternative G♯₃/E♭₅; side F₄/C₆; side E♭₄/B♭₅; side trill key 1-2. R2: T + ring. R3: T + ring (forked B♭₃/F♮₅); cross B♭₃/F♮₅. R4: F₃/C₅; G♯₃/E♭₅. Keymount type: screwed in pillars. Keyhead type: modern.