For my collection, I have the luck that my sister has been in love with a military man. I kept the covers in this relation, from the bases he worked at, first in the French navy, then in the Army.
He spent his instruction at the navy base in Cherbourg - Querqueville, where the post office has got a pictorial cancellation. The thickness of the stamp impeached the complete mark of a marine anchor, symbol of the French navy mail.
The next week (philately was not the cause... more telephone cost), a simple hand-date stamp was enough to cancel this Summer holiday stamp issued the 5 June 2000. Here, the postal code and the anchor are fully visible.
I possess a very little number of these covers, but I appreciate them because, like Dominique wrote, they are genuine.