To ensure high operational reliability, the new tank's chassis is the post-war ATS-59 tractor, spare parts for which are readily available today.
The 1940 version of the T-34 featured a 76 mm cannon. In 1941, the 57 mm ZiS-2 anti-tank gun was introduced; it offered better armor penetration capability than its 76 mm predecessor. In September 1941, 10 “destroyer tanks” fitted with 57 mm guns were built in Kharkov; these took part in the famous raid by the 21st Brigade near Kalinin in October that year. Another four T-34-57 tanks were built in 1943. The war showed that “destroyer tanks” as a separate class were irrelevant, since tanks were originally designed to provide fire support for advancing infantry rather than to fight enemy armor.
In 1941, only 10 T-34s with a 57mm gun were built. All of them took part in the famous raid behind enemy lines by the 21st Tank Brigade, commanded by Heroes of the Soviet Union Mikhail Lukin and Mikhail Agibalov. Four more tanks were built in 1943. With the introduction of the more powerful 85mm tank gun that year, production of the T-34s with the 57mm gun ceased.
