FT17 cast turret 37mm

The Renault FT-17 (Automitrailleuse à chenilles Renault FT modèle 1917) light tank was among the most revolutionary and influential tank designs in history. It was the first tank with an armament in a fully rotating turret. Its configuration with the turret on top, engine in the back and the driver in front became the classic one, repeated in most tanks until today.
The tank was widely used by the French and the Americans in the latter stages of World War I. After the war, FT-17s were exported to many countries (Poland, Estonia, Lithuania, Romania, Yugoslavia, Czechoslovakia, Switzerland, Belgium, The Netherlands, Spain, Brazil, Turkey, Iran, Finland and Japan). As a result, FT-17 tanks were used by most nations having armoured forces, invariably as their first tank type, including the United States. They took part in many later conflicts, such as the Russian Civil War, Polish-Soviet War, Chinese Civil War and Spanish Civil War.
FT-17 tanks were also used in the Second World War, among others in Poland, Finland and France, although they were completely obsolete by then.