T-18 (MS-1 - small escort) - Soviet light infantry tank of the 1920s. Created in 1925-1927. It became the first Soviet-designed tank. Serially produced from 1928 to 1931, 959 tanks of this type were produced in just a few versions, not counting the prototype. In the late 1920s - early 1930s, the T-18 formed the basis of the Red Army's tank fleet, but was quickly supplanted by the more advanced T-26.
It was used in battle in the conflict on the Chinese Eastern Railway, but in 1938-1939, the obsolete and extremely worn-out T-18s were mostly decommissioned or used as fixed firing points. In an insignificant amount, these tanks were still in combat readiness in the troops by the beginning of the Great Patriotic War and were used at its initial stage.