I know it's very hard to see in this one picture, but they are actually very rare fiber board (Papier maché) helmets.
When looking very closely, you can see there's actually no deformation and the trained eye can also see the different structure of the vulcan fiber front visor and the fiber board body. The neck guard is also made in vulcan fiber (not visible in the picture).
You can also notice in the following pictures that the liner is made of ultra thin artificial leather (don't know the exact English word) and that the liner cord is very flimsy. The chinstraps are also extra thin.
The helmet body is made of composed fiber (chopped cart board mixed with glue) and because of that it looks this lumpy instead of smooth like a normal liner usually is...
The ersatz of the ersatz one would think, but in fact these helmets are much better and more comfortable than their leather brothers... They are much lighter, keep their shape much better, are more water resistant and seem more resistant against time and the elements...
Here are the other pictures...
Adler 1
PS Both helmets have 5 holes in the spike's neck and they, but that's nothing special I would say... They are different sizes, but their are no stamps or marks visible on the entire helmets...
Left helmet
View attachment 4
View attachment 3
View attachment 2
View attachment 1