Designed in 1934–36 by N. Astrov's bureau at Factory No. 37 in Moscow, the T-38 was a development of the earlier T-37, based in turn on the French AMR 33 light reconnaissance tank. The tank was powered by a standard GAZ (Ford) engine and was cheap to produce. Buoyancy was achieved by the large-volume hull and large fenders. In water, the vehicle was propelled by a small three-bladed propeller mounted at the rear.