A small number of the earlier version were converted into using folding stock, sometimes referred to by the Allies as the Type 100 Navy, which was made for parachutists.
It was made in two basic variants referred to by American and British observers as the Type 100/40 and the Type 100/44, the latter also known as the Type 100 (Simplified). The Type 100 submachine gun ( 一〇〇式機関短銃, Hyaku-shiki kikan-tanjū) was a Japanese submachine gun used during World War II and the only submachine gun produced by Japan in any quantity.
