900 mark and an unknown mark

[Joerg]

I found this mark in the Internet. It is unknown to me and I wanted to identify it. But no success.
Do you have any ideas?



The mark below seem to be "900".

Regards

Jörg

Here the object. With electrical connection. So should be not so old, but I am confused.

[tolly123]

I believe it is Swiss but struggling to find the makers mark online