by mk1rceme on Thu Jan 10, 2019 6:52 pm
From what I was told, these US camo helmets were done during and after the war to mimic the german camo pattern that was used on stahlhelms during the war. So, it could be, or not that it was done during the war. Personally, I would say post 1918 applied.
I found a link that will explain it better than me.
https://alexanderandsonsrestorations.com/truth-camouflaged-helmets-great-war/