I believe this is an Adrian helmet, although I cannot be entirely sure.
I bought it in France a while back, for just 20 euros. The metal clasps that hold the liner are only 3 in number, as one has been snapped off, and the helmet itself has been repainted extensively. Coats of paint are in this order: Original blue, black, field green. The badge is an infantry one, I believe, but is not normal as it is on a shield.
Can anyone elaborate on this? Thanks! An estimated value would be splendid, by the way.