This unusual instrument from Czechoslovakia is actually a form of harmonica. It is 8 ½” long, and according to the seller:
It has a metal mouth piece and four independent buttons to control the flow of air. You cant see the harmonica as it is actually inside.
I don’t know if this 4 key harmonica was ever intended as a real musical instrument, but it is certainly an interesting saxophone collectible.
The 4 key harmonica was perhaps made by the same Czech company that made this 8 key variety on the next page. It has the same brass wind-type mouthpiece, although some of the finer details are a bit different. Because there was a lot of copying of not only real instruments, but also toy instruments like whistles and kazoos, back in the early part of the 20th century, these 2 little sax-shaped harmonicas could easily have also been made by 2 different manufacturers.