Sure seems "UNUSUAL"

[MadMax13]

http://cgi.ebay.com/GERMAN-ERZATZ-PICKELHAUBE-PATERN-1915-MUSEUM-QUALITY-/150466901093?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item230886b465

 

[Tony without Kaiser]

THIS HELMET HAS THE REMOVAL SPIKE SPLIT COTTERPINS SO THAT IN THE FRONT TRENCHES, THE SOLDIER COULD REMOVE THE SPIKE WITH HIS BOOT KNIFE.

Where do sellers get this from? Hilarious!

 

[J.LeBrasseur]

C'mon Tony, I thought that was common knowledge, that is why so many boot knives have nicks in the blades

A little humor on a Wednesday morning!
James

 

[Gustaf]

Now to comment on the helmet, the chinstrap post reenfocements are not something I have seen on an ersatz helmet, I can not tell what this helmet is made of, and it looks like it may be pvc. Museum quality is usually a key word for reproduction.
Gus