Tank origin

Developed in 1934 by the tank bureau within the economic division of the Joint State Political Directorate, the project was designed to replace the T-28. The working prototype was produced in Leningrad, at the Experimental Kirov Plant (Plant No. 185) in 1935, under the supervision of engineer N. V. Tseyts. The vehicle was provided with a wheeled and caterpillar propulsion system, and entered service in February 1936. Its production was started at the Leningrad Kirov Plant, but only a few vehicles were built before production was discontinued due to complex construction and an unreliable chassis.