On ne Passe Pas French WWI Sweetheart Tank Necklace Book but that is likely because

but that is likely because the factory added backpack straps cover the area where the maker marking is usually found

Its very similar to the German straight shovel and would have been reissued to the Wehrmacht after the fall of Holland

I don't believe any of them ever had a very good paint job

but there are a few photos floating around that show freezing soldiers cramming bundles of sticks down the top opening to burn

Without the markings

On ne Passe Pas French WWI Sweetheart Tank Necklace Book but that is likely becauseVintage WWI French sweetheart necklace with tank. "On ne Passe pas" (they shall not pass) was first used in the battle of Verdun in 1916 and was later used by troops defending the Maginot Line. It is unmarked. There is some discoloration patina on both the charm and the chain.