Field tests of the British AEC Mk.I armoured cars in Africa showed that its weak 40 mm cannon was far from enough to go toe to toe with the German Pz.III and Pz.IV tanks. Engineers at the AEC company proposed a new version of their armoured car with strengthened armament and a more powerful engine. The new wheeled military vehicle carries the renowned British 6-pounder 57 mm gun. The vehicle’s crew was increased to four and its top speed to 40 mph (65 km/h).