Hello, I found this M15 Adrian helmet in France at a small dealer. He told me it is a early version made by the Japy factory which you can identify by that it has no rivets on the side and chinstrap. However I can not find any example with a sewn fixed chinstrap like the one I have, rather than a riveted chinstrap which every helmet has. Does anyone know anything about this?
(Sorry if the pictures are unclear the flash on my phone isn't working, the helmet is lighter in color.)