Renault R40 Light Tank with 37mm SA38 Gun
In the early stages of WWII the Renault R35 was the most numerous of French tanks. By 1937 it was clear that the original suspension system was flawed. It was improved in 1940 by an AMX system with twelve wheels and six vertical springs. At the same time an improved radio and the long barrel L/35 37mm SA38 gun were fitted in an adapted APX-R1 turret. The new variant was designated "Char léger modèle 1935 R modifié 1939" but was more commonly referred to as the Renault R40.