Mystery makers mark c.1900 bracelet ?

[Peartree]

Hi, do you recognise this “MuS” makers mark? It is on this extraordinary bracelet. The bracelet carries 1872-1901 Austrian import mark. So the piece is remarkable for its age and probably dates to c 1900 and looks like a Wiener Werksatte style piece. But presumably is not Austrian. Perhaps Czech or German? Weirdly it also carries marks for French gold import (but seems to be silver gilt). All advice welcome! Thank you Anthony