The GAZ-AAA (4M) was a self-propelled anti-aircraft truck developed by the Soviet Union in 1938, based on the GAZ-AAA truck platform.
[1] In 1928, Fedor Tokarev developed a quad mount for the 7.62×54mmR PM M1910 machine gun for use as a light anti-aircraft weapon, which was adopted in 1938[2] as the 7.62mm M.1931 4M ZPU.
[3] The 4M ZPU was mounted on a GAZ-AAA truck to create a mobile AA weapon.
While effective against low-flying targets due to the high rate of fire, this setup was only used as a stop-gap measure until more dedicated anti-aircraft weapons could be developed and fielded.
[4] Later versions of the anti-aircraft truck equipped the 12.7×108mm DShK machine gun.