The BT tanks were lightly armoured but produced in large numbers to provide support for the infantry - over 5,000 BT-7 were produced.Weighing in at only 13.9 tons the BT-7 was a fast tank with a max speed of 53kph. BT-7s were up-armed with a 45mm cannon replacing the earlier 37mm gun. The BT-7 Experimental was fitted with a short recoil 76.2mm gun model 1927 as well as a 7.62mm DT machine gun in the turret and another on the front glacis plate. This version never entered production.