Here i have for your pleasure, A Belgian M51 (Airforce issue), this one is dated 1953 , and is a pre 1971 model as the liner is a resin layered fabric , very similiar to the US M1 style. After '71 they were produced in molded thermoplastic.
I have been informed from a another source that the Belgian Airforce classed these as a Model T-21, Anyone out there know if this could be true??
More European helmets to come,watch this space!