update: added modified models, mounting can be done with M3 bolts
In my hometown Hasselt they introduced new address numbers. This is a holder for this number. Note: for mounting the lid you'll need M2 bolts
More info:
https://www.vvsnv.be/hasselt-reflecterende-huisnummers/
https://www.hasselt.be/nl/huisnummers
maybe also suitable for address numbers of these towns: Geel, Lanaken, Wellen, Riemst, Zutendaal, Bilzen, Peer, Hechtel-Eksel, Roosdaal,…