I can't write "slip joint" that would mean something totally different in French...

I wrote "canif camping" that's the canif that set a problem. The young lady was over-zealous. I tried to explain there's the law and the spirit of the law, she just gazed at me!. Next time I won't ask for the sticker (you have to ask for them) and send as a plain letter as usual. She confirmed me it is legal. Or I'll check with the other postman! For the moment the parcel is waiting in NY.