What is this Antique Brass Instrument on display at the Musical Instrument Museum in Brussels, Belgium? - Music: Practice & Theory Stack Exchange

Does anyone know what type of instrument this is? It looks like some type of Euphonium, but obviously very different.

The Musical Instrument Museum – Brussels, Belgium - Atlas Obscura

MIM MIM

Musical Instrument Museum, Brussels - Wikipedia

Sampling Tea Musicus Society

Explore a vast array of Instruments from music cultures from around the world in the Musical Instrument Museum (MIM) in Brussels, Belgium.

File:Stringed instruments - Musical Instrument Museum, Brussels - IMG 3919.JPG - Wikipedia

Musical instruments museum brussels hi-res stock photography and images - Alamy

Antique brass instrument on display at the Musical Instrument Museum in Brussels

MIM MIM

Visiting the Musical Instruments Museum in Brussels - Bright Nomad