formed from a single armour plate. The Czech machine guns were changed to Hungarian 8 mm Gebauer 34/40.M guns. The overall weight was also increased to over 18 tonnes. Variants The Turán was produced in three versions – Turán I, II and III. The Turán I was the original medium tank with the 40 mm gun. The gun, the standard Hungarian light anti-tank gun, could fire the same ammunition as the Bofors 40 mm anti-aircraft gun. The turret was of riveted construction. Between 1941 and 1943 a total of 285 tanks were produced. The combat experiences of 1941 made Hungary realize that the 40.M Turán (Turán I) which was at the time still under development and construction would not meet the expectations of modern medium tanks. The General Staff of the Hungarian Army changed the second order of 309 medium tanks to 87 medium and 222 heavy tanks armed with a 75 mm gun. This order was later changed again in 1941 to 55 medium and 254 heavy tanks. The General Staff also declared that the new heavy tank must be constructed from those Turáns already built without changing the engine and the weight of the new tank must be equal or close to the heavy tank. The mentioned heavy tank would become the Turán II. The prototype of the heavy tank and the new 75 mm gun was ordered from the Institute of Military Technology of the Hungarian Army (HTI) in 1941. The HTI did not have any gun designer nor production departments so they had to choose from an already existing gun and try to modify it. The engineers chose the 18.M field artillery gun – 8 cm Feldkanone M.18 – which had been in service since World War I. The HTI ordered the modification of the gun to be done by the Swedish Bofors company, which willingly accepted. Both the modifications of the chassis – armour thickening to 50 mm by riveting extra 20 mm armour plates on the frontal armour and lower glacis, changing the driver's hatch from a single door which opened to the right to a two-piece folding door which opened to the front – and the prototype of the new gun and turret were finished in January 1942, the new turret was finished in February 1942. The new 75 mm gun was the first Hungarian tank gun with a horizontal semi-automatic sliding block.