Comparing: T1 Heavy Tank vs. Excelsior vs. KV-1

Development of the T1E2 started in the U.S.A. in May 1940. The vehicle was designed as a heavy tank. The distinctive features of the vehicle were a cast hull and hydromechanical transmission with a double-disc hydraulic converter. Later, the tank was designated M6. A total of 9 vehicles (1 of which was experimental) were produced. The tank never saw action.

At the end of 1942, the Churchill tank's armament was deemed insufficient. New tanks, the A31, A32, and A33 were developed as new infantry tanks. The A33 was developed by the English Electric Company. The LMS Company participated in the development of suspension for a new tank. Two vehicles, which differed greatly from each other, were manufactured. The A33 was set to go into production, but in 1943 the decision to cancel mass production of the Churchill was reversed, and the order for the A33 was not placed.

Development started at the end of 1938. A prototype was produced in August 1939. The vehicle first saw combat in December 1939 at the Mannerheim Line. The tank was mass-produced from March 1940 through August 1942, with a total of 2,769 vehicles manufactured.