Hallmarks on a silver foldable comb

I have this silver (? ) foldable moustache/beard comb.
Received it from my mother, but we have no idea what country or time period the comb came from.
We are from Brussels, Belgium.
Maybe this could help to identify some aspects of the comb:
There are two hallmarks: the number 0.5 in a square and the letter A with a heart beneath is in a rectangular mark.
I can’t find information on what these hallmarks mean.
Some pictures of the comb and the hallmarks are included.

Thank you for looking at this!

Kind regards,



comb marks