Very nice helmet Coert, congratulations on adding it to your collection! :thumb up:
I once had an example that was depot reworked that I sold to Amy back in late 2006 or early 2007 that I still miss having.
It had a fluted spike on it with the cloverleaf cross base, and old plugged holes behind the front plate which were done by the depot arsenal repair shop. A collector friend of mine bought it from a family about an hour away from where I live, along with a nice common M15 Prussian helmet. Both helmets were missing the chinstraps and kokardes. I had a bit of difficulty in convincing my friend that the fluted spike belonged on the Hessian helmet, and not the Prussian one as he had found them from the family. I suppose they were played with over the decades, and the spikes inadvertently got switched at some point of time. I finally convinced him, and switched the spikes back to their correct helmets.
Best Regards,
Alan