Dutch M53 helmet 1985 used by the Air Force or "Luchtmacht" (part 1)
The Netherlands used the same helmet shells, same green color for all their forces, even for the Navy the helmet shells would be green. I know some of the navy helmets would be painted red, yellow or any other color but this was done by ship crews, however these helmets were issued in green.
The shell is made by VDN as shown by the heat stamp in the inside rim.
VDN = Vereinigte Deutsche Nickel-Werke.
2/85 = Februari 1985
VDN made helmets for several countries like this Belgian M1 helmet clone for the Air Force
The Liner in this helmet is Air Force grey. see liner used by the Air Force part 2