Not sure about the use of these "chromed" helmets ... but there seems to be lots on the market at the moment!!!
The liner with the yokes and chinstrap is a nice Korea/ Vietnam era M1C paratrooper!!!
The helmet itself has a chinstrap that looks a very simple affair!!!!
All true chrome parade Helmets usually always carry the white leather chinstrap,they themselves are ultra rare and are seldom seen in todays market which leads me to believe that most have been altered in some way,the money is in the white leather not the chromed pot itself,this pot is from 1970-76 period.
I know about that the chrome helmets were used by bands at least.
With best wishes
Searching for information, material and items of RAD "Hessen-Süd" (where my father was probably in K-Einsatz, combat engagement, in the Alps in 1945), IR 87 (where my grandfather was during campaign in France in 1940), Gardegrenadierregiment Nr. 3 "Königin Elisabeth" (where my grand-uncle was at Craonne/Chemin des Dames in France in 1917)
I own a 51 McCord chrome but it too came without chinstraps and only the normal p64 type liner so was most likely a Nam era honor guard but again the all important leather was missing.................