The AH-IV was designed to replace the vz.33 tankette. The AH-IV was given a turret for better all round field of fire and the AH-IV was armed with a 7.92mm ZB vz35 or vz37 heavy machine gun. The tankette had a crew of 2 and served with Romania, Sweden and Iran during WWII. The Romanians were sold 36 AH-IV-R on 14 August 1936. The R-1 was a Romanian design under license but only one prototype was ever made. The Romanian vehicles were used during Operation Barbarossa in 1941.