Here's an uncleaned helmet straight from a family. Unfortunately it wasn't taken care of very well over the years since it came to the USA after WW1.
With some patience and TLC it should come out looking a little nicer than it currently does.
I'm amazed that it still has the original chinstrap and kokardes, which are almost always missing on these helmets when found.
I can see some faint markings under the curled area of the back visor. Hopefully it's marked "K.B.A.G. 1916". Soldier's name is penciled inside the lining. Remains of an old newspaper are stuck to the back visor. As mentioned, this poor old thing wasn't given the best of care over the years, unfortunately.
I look forward to your comments.