The BA-3 was a heavy armored car developed in the Soviet Union in 1933, followed by a slightly changed model, the BA-6 in1936. Both were based mostly on the BA-I, the most important difference being the new turret, same one as in the T-26 m1933 and BT-5 tanks, and also equipped with the45 mmmain gun. Around 180 BA-3 cars were built until production ceased in 1935. Most of BA-3 production was based on the Ford-Timken chassis, a 6×4 modification of the US Ford AA 4×2 truck, but the last batch was built on a Russian version of the same chassis - GAZ-AAA, continued to be used in BA-6. The biggest limitation of the BA-3 was mobility, limited to roads or very hard ground, the result of its unnecessarily large weight. The innovation that slightly improved mobility were the auxiliary ("Overall") tracks that could be fitted onto the rear tandem wheels, effectively converting the car to half-track.