I believe is the M-1 helmet that was used anywhere from WWII era to the korean or vietnam wars but I am not positive which era it is from .There is a name inside , Kvetkosky F R(in two places There is some faint stamped numbers that looks possibly 366A.(the 3 looks very faint) It is in good overall condition ,It has a swivel bale,No liner . There is average signs of age and use. Abit of light surface rust inside.
Can anyone help me out with dating this?