The T-18 light tank (also called MS-1, , 'First Small [Vehicle for] Support') was the first Soviet-designed tank, produced in 1928–31. It was based on the Renault FT-17, with the addition of a vertically sprung suspension. Production took place at the Leningrad Obukhov Factory (later renamed Bolshevik Factory), starting in May 1928. The first batch of 30 tanks were found to have serious technical problems. After several stops, production of an improved T-18 with a better forty horsepower engine and added turret bustle proceeded from 1929 to 1931, with a total of 960 tanks built.