Comparing: O-I vs. ARL 44

Development of the superheavy tank was started after the Battles of Khalkhyn Gol in 1939. The vehicle was designed as a maneuverable fire unit that was unprecedented in scale—its hull alone weighted 100 tons. Only one prototype was built, without a turret and made of construction steel. Trials were discontinued due to the unreliable engine; at the end of 1944, the prototype was scrapped. The 15-cm howitzer was to be mounted on the tank after the assemble.

Development of the vehicle started while France was still occupied by the German forces. It was an attempt to use the obsolete B1 Bis chassis and fit it with a modern, more powerful gun. The project was finished by the Atelier de Construction de Rueil Design Bureau. A total of 60 vehicles were manufactured. However, the tank was considered unsuccessful compared to similar foreign vehicles.