If you loosen the string on the back, it will expand to about 57 cm. It is made using the military uniform material of the 45th type.International Buyers - Please Note. The item "WW-2 Imperial Japanese school hat military cap real military" is in sale since Friday, July 10, 2020. This item is in the category "Collectibles\Militaria\WW II (1939-45)\Original Period Items\Japan\Cups". The seller is "ryomtakeut-0" and is located in Osaka. This item can be shipped worldwide.