This is a M40 single decal reissue helmet by maker NS64 (being maker Vereinigte Deutsche Nickelwerke AG, Schwerte (NS)).
The helmet is in as found condition. Nothing oiled, cleaned or altered. It was recently found in Denmark and has since the war been in privat non-collectorshands and has never been on the collectors market before. A true woodwork find. The condition is honest and that shows. There is some minor, typical age rust, but nothing disturbing and this actually adds character. The decal is for the most part present as its the liner and liner string.
A very cool original helmet in untouched condition.