The heavy Char B1 bis,dated from the late 1920s and was intended to be the French Army's main battle tank. It was considered an advanced vehicle, while its 47mm anti-tank gun, which armed a small one-man turret was considered the best gun in its category.Production was slow : by 1940 only 400 had been built.The B 1 bis' potential was, however, wasted as they were committed to piecemeal battles and not concentrated as the German did.