Soviet helmets during World War II
Over the course of World War II the Soviet Union employed three main helmet designs; the M-36, the SSh-39, and the SSh-40, each being designated with the year in which they were introduced. Standard practice was to stamp the size, location, and year of manufacturing on the interior of the helmet.
Adrian
The French Adrian helmet was used by the Imperial Russian and then the Red Army until the M36 started entering service. However large stockpiles were kept and were issued during the mobilisation, especially to second line units.
M-36
The M (model, or model) 36 was designed by Aleksandr A. Shvartz, and began production in 1936. Its large front rim and wide flares over the ears provided good protection for the wearer. The German M35, introduced a year before the Russian M-36, served as a model for the development of the M-36. The M-36 was also fitted with a comb on top, which allowed for ventilation. There were also apocryphal claims that the comb was designed to deflect saber blows.