Often the chassis for these conversions came from tanks or artillery tractors and two such vehicles were the US built M7 Priest and M12 gun motor carriage supplied to Free French forces during World War II.

During the 1950s France began a rearmament program to replace both of these guns to provide mobile artillery support for their mechanized divisions.

The new vehicle had the same five-wheeled torsion bar suspension with front drive sprocket, rear idler and three return rollers as the AMX-13.

An all-welded box-shaped steel superstructure was mounted to the rear of the vehicle to provide 360° of protection from small arms rifle fire and shell splinters.

[3] The primary armament for the vehicle is an Obusier de 105 modèle 1950 howitzer with a wide range of elevation -4° to +66° but with limited traverse 20° right and left.