that is a M42 helmet, the lighter color appears to be Krigsmarine but hard to tell really, majority of these were painted a dark ruff coat green, or Dunkle Grun, but who knows with it being as old as they are getting to be. With so many variations in paint an being exposed to what ever caused that heavy rust on it. Every mint condition 42 I've seen has been the dark green though, I use to collect german helmets an had about 70 at one time, with two kids in college now I've gotten rid of most of them an had to stop the collecting, I do have a mint 42 I bought in 1989 in Berlin at a flea market when me an the wife spent a week there for New Years after the wall came down, was a very cool time to be there an will never sell that helmet.
Chris