Comparing: Object 907A vs. STB-1

The decision to start development of a next-generation medium tank was made on July 13th, 1953. Development was carried out by Research Institute No. 100. The project was submitted in March 1954, and at the beginning of 1955 the hull of the new vehicle was tested for shell resistance. However, later the project was canceled.

In the early 1960s, Mitsubishi started development of a new tank that complied with government requirements for armament and defense. The first two prototypes of the STB-1 were manufactured in September 1969 for trials. In 1970 the prototypes were shown to journalists and participated in a military parade.