I' ll try to put up a thread for Flemish regalia.
I'll start with what I have, because it is so very little, feel free to add what ever you encounter or come by.
Politicaly speaking the Flemish matter has always been quiet complex.
Before and during WWII maybe the most.
You will see many organisations that were willing to collaborate with the Germans but several had certain restrictions.
That is how different organisations went up into a other and so on.
The Flemish Hitler Youth was only created at the end of 1943 and so didn't last long! I don't know how much members it had but some say not more the 1000, including kids of German citizends that were stationed in Flanders.
And I am pretty sure these buttons were used on HJ Flandern uniforms.
The construction is completly similar to a German uniform button made in Antwerp during the war.
And knowing what I know and were it comes from, make me think HJ Flandern.