Nearly 40 years ago a friend of mine in the Seattle area picked this up from a man who had served with the 187th PIR. He was part of the contingent of "Rakkasans" at San Pablo Airfield (Leyte, PI) when the Japanese Army's 3rd Parachute Regiment launched an airborne assault during the night of December 6th, 1944. Additional objectives of the assault were the airfields at Buri and Burauen. I think the 187th is the only American Airborne regiment to have been assaulted from the air during WWII. This helmet was taken directly from one of those 306 Japanese Paratroopers.
I was fortunate enough to acquire the piece a couple years back. To me, the most historical Japanese Paratrooper helmet I have come across. I have owned three others over the years but to me they (although rare of course) were simply military surplus compared to this one.
This is a first model helmet (leather vs. cloth flaps)
Notice how it has been camouflaged for a night operation (by what appears to be wood stain or gun oil). It definitely is NOT post war applied lacquer or something like that.