Back-of-book issues are always fun to receive, as you usually have to do some detective work to find out details and history of the item. Below is a mystery item I assume to be from France. I hope that french collectors could help me with this one as I have run to an dead end.
What I do know is… Text on the stamp is about quality regulation (Qualité réglementée) and export (Exportation). So this could be some kind of quality control label for exported products… Plougastel is an area in northwestern France… I have also googled an (old /removed) eBay item with description stating that something with similar text/description would be an rare (something I doubt very heavily) item.
So please, help me to find out what this is.