The rugged Panzer kampfwagen III was used in all theaters by the German army in WWII and was well-liked due to its reliability. However, the size limitations of the tank's chassis meant that armament upgrades were limited and its usefulness as a battle tank diminished as the Allies produced more advanced and powerful tanks. With this realization, the final variant of thePz.kpfw.III, the Ausf.N, was modified into an infantry support tank armed with the short-barreled75mm gun from the Pz.kpfw.IV, which was being upgraded with more powerful guns. Beginning from June 1942, 700 of these Ausf.N variants, also known as Sturmpanzer III, were made and were often assigned to independent Panzer Battalions to protect the heavier Tiger tanks. The5mm Schurzen armor skirt modifications were added from the spring of 1943.