Generally considered the best all-around medium tank of the Second World War, the Soviet-developed T-34 may have had cruder machining than German or American tanks, but it was reliable, easy to manufacture, and better armored than German, British, or U.S. designs. It went into production in September 1940, with a short-barreled 76.2 mm gun, quickly replaced by a longer, higher-velocity gun a year later. It had a diesel engine, making fire much less likely than with the gasoline-powered U.S. M4 Sherman and faster than German tanks.
The T-34/85 an upgrade T-34 equipped with a more powerful armor and cannon. It began to be replaced with the T-54 (tank) in 1949, but remained in service worldwide. T-34 tanks, in the early Korean War were largely immune to then-standard U.S. infantry antitank weapons.