The Renault YS was a version with a large superstructure but without turret, serving as a higher command vehicle. The specifications for such a type had been issued on 9 January 1931: it was then named the "Type M". Renault had built two prototypes of boiler plate, based on the AMR 33 chassis, in 1933. General Darius Bloch, head of the technical section of the supreme command, had formed a favourable opinion on these in September 1933 and during a session of the "Conseil Consultatif de l'Armement" in January 1934 had desired that a dozen be acquired. On 10 April 1934 the order was signed for ten "voitures de reconnaissance tous terrain blindés", to be delivered before 31 December 1934, the uncommon term "all-terrain armoured reconnaissance vehicles" intending to obscure the fact that they were command vehicles. They had the factory designation Renault YS.