The T2E1 was produced after the trials of the T2 and T5 in April 1934.4 It now had the better vertical volute suspension. It was armed with a .30 and .50 caliber Browning machine guns in the turret, which was the width of the hull. An additional .30 MG was installed in the front of the hull. This vehicle was standardized in late 1935 and put into production at the Rock Island Arsenal and designated the M2A1.8
The T2E2 had 2 turrets installed, with each containing an MG. This was standardized as the M2A2 and put into production in 1938.