In 1942, the demand for mobile direct artillery support of the infantry was still unanswered in the Red Army.
The first installation of the ZiS-3 76mm divisional gun on the lengthened T-70 chassis, the so-called »SU-12«, later SU-76, at GAZ and plant N^o.38 at Kirov during winter 1942/3 resulted in a desaster.
Fortunately, the Red Army had recently captured hundreds of German StuG and Pz.III chassis at Stalingrad which could be used as a stopgap.
Eventually, GKO gave the production order to plant N^o.37 at Sverdlovsk, part of »Uralmash«.
In February 1943, the designers at plant N^o.37 mounted a box-like, side-angled fighting compartment on the German Pz.III chassis and chose the 76.2mm F-34 gun as main armament.
One roof hatch, a two-piece rear hatch and, on 20 command vehicles. a German copula granted access and later two additional fuel tanks were installed to the rear engine deck.
As proper ventilation remained an unsolved problem, the compartment roof was later removed completely.
In total, roughly 1200 vehicles were produced between May and November 1943 and proved rather useful during the decisive summer battles of summer 1943.
As Pz.III trophy chassis amount declined, the production was finally stopped for the lack of spare parts.