The turrets were produced separately. First the ST3 turret (Schneider Tourelle 3) had been tested in 1933; then the ST2, at the time seen as a possible standard turret for all heavier tanks, was considered but finally a choice was made to use the APX1, originally developed for the Char B1, costing ₣ 200,000.
The turrets were produced individually. The ST3 turret (Schneider Tourelle 3) was tested in 1933; then the ST2, considered a potential standard turret for all heavier tanks, was evaluated but ultimately the APX1, originally developed for the Char B1, was chosen at a cost of ₣ 200,000.