The AB 40 armoured car was devised for the Italian Royal Army in the late 1930s, to replace the old Lancia models. The vehicle was innovative at the time, being a four-wheel drive with separate suspensions and two driving positions. The armoured car was fitted with two 8mm machine guns in the turret and another in the rear of the hull, but was only built in small numbers for evaluation purposes, as development of the more sophisticated AB 41 was already underway. A few of the models were turned into tracked patrol vehicles as the wheels could be replaced with rail wheels and relative braking systems. A few of these vehicles were used in Yugoslavia by the Italian forces and, later, by the Germans.