I don't know the details, but there is no doubt that it belongs to the Japanese army at the time of World War II. The item "World war WW2 original imperial japanese army combat helmet Military" is in sale since Friday, May 1, 2020.
This item is in the category "Collectibles\Militaria\WW II (1939-45)\Original Period Items\Japan\Other Japanese WWII Orig Items". The seller is "no_spe-94" and is located in tokyo-to. This item can be shipped worldwide.