In 1942, inspired by the success of the German Sturmgeschtz III, the Hungarian general staff decided to build an assault gun. The design was based on tue 40M Turan I chassis, replacing the turret with a fixed gun in an armoured superstructure. Two designs were made; the44M Zrinyi I and the 43M Zrinyi II. The Zrinyi I was designed as a tank destroyer, armed with a long-barrelled 75 mm gun, but only a single prototype was made. The Zrinyi II, armed with a 105 mm howitzer, was designed for infantry support. A total of 60 Zrinyi II were build.