UM MT 689-01 Artillery Self-Propelled Mount AT-1 (1935) (plastic tracks)

The AT-1 was a prototype Soviet self-propelled gun from the Second World War. The first prototypes were built in 1935, but the car never entered mass production. The AT-1 was powered by a single engine carburetor with a power of 90 HP. The original version of the vehicle was armed with a single 76.2 mm PS-3 tank gun and a single 7.62 mm DT machine gun.

At the turn of 1932 and 1933, in the design office at factory No.174 in Leningrad, the concept of creating a self-propelled gun using the chassis and hull of the T-26 tank was born. However, the first prototype was built relatively late, probably due to the desire to take into account the flaws revealed during field tests by a very similar design - the SU-1 gun. Nevertheless, the trials and tests of the AT-1 revealed many shortcomings of the design and the overall underdevelopment of the vehicle. It was decided to remove them and change the main armament to the L-10 cannon, also with a caliber of 76.2 mm. However, work on the AT-1 dragged on until 1938, and despite the initial order for 100 of this vehicle, it was canceled in favor of the modified BT-7.