Тяжелый танк КВ-2. Первый опытный экземпляр
After the troubles the Soviet Army faced during the Winter War with Finland, while overcoming the "Mannerheim Line", it was decided to design a tank with a 152 mm caliber weapon. In the short term (2 weeks), a team of engineers from the Kirov plant designed the turret with installation of the M-10 howitzer for the KV tank. The new artillery system had a shorted barrel and was designated as MT-1.