Two german buttons to identify

[Christophorus]

Good morning everyone,
I need your help to identify these two buttons (15mm & 19,1mm):
The bigger is marked "AD" on the face and "ges gesch H.S.B." on the back.
Why not a RAD button but I don't know...
Thank you for your help,
Cédric

[militarymania]

i think these are BDM buttons,,

[bichon]

Hello

what is this german button ?

thanks for answers
cordially
Didier