The 75 mm Reșița Model 1943 was an anti-tank gun produced by Romania during World War II. It combined features from the Soviet ZiS-3 field/anti-tank gun, the German PaK 40 and the Romanian 75 mm Vickers/Reșița Model 1936 anti-aircraft gun. It saw service against both the Soviets during the Jassy-Kishniev Offensive and against the Germans during the Budapest Offensive and subsequent operations to clear Austria and Czechoslovakia. According to British historian Mark Axworthy, the gun could be considered the most versatile of its class developed during World War II, outperforming Soviet, German and Western counterparts. Development Development began in 1942 of a dual-purpose field and anti-tank gun that could be built in Romania to replace the collection of obsolescent field guns currently used and upgrade their anti-tank defenses of the army. To speed development Colonel Valerian Nestorescu suggested combining the best features from the guns already in service in Romania, Germany or captured from the Soviets. Colonel Nestorescu was selected to produce a prototype to be built at the Uzinele și Domeniile Reșița in Reșița. Three prototypes were built combining various features and trialled against the ZiS-3, a Reşiţa-built copy of the ZiS-3, the Pak 40 and the Schneider–Putilov Model 1902/36 field gun in September 1943 and the third prototype had the greatest armor penetration. It was adopted as the , commonly shortened to 75 mm Reşiţa Model 1943. Description The gun combined the muzzle brake, recoil and firing mechanisms and split-trail carriage of the ZiS-3, the barrel, rifling and cartridge chamber of the Vickers/Reşiţa Model 1936 anti-aircraft gun and the projectile chamber of the Pak 40. It had a gun shield that consisted of two plates separated by a gap. It had only 680 parts, almost as few as the 610 of the ZiS-3, but far fewer than the 1200 of the Pak 40. It had a higher muzzle velocity and thus greater penetrative power than the Pak 40. It therefore combined virtues of both the ZiS-3 and Pak 40. 1100 guns were ordered on 10 December 1943 from Uzinele și Domeniile Reșița, Astra in Brașov and Concordia in Ploiești. The 75 mm Reșița Model 1943 fired a armor-piercing shell at . Penetration test consisted of eight armored shields with a thickness of 10 cm placed as follows: the first four were 300 meters (arranged at an angle of 30º), the other three at 500 meters (same angle) and