The first prototype of the armored vehicle was in development from 1932 through 1934 under the supervision of engineer Gendron. The second prototype of 1935 successfully passed trials. The project was almost canceled due to insufficient funds, but the SOMUA company continued its development. An improved prototype was produced in 1938 and successfully underwent trials from 1938 through 1939. It saw service but never entered mass production due to delays with turret supplies.