Panzer III Ausf H number 615
In January 1939, an order was placed for 759 units of the Ausf H model. This model was the first to be equipped with the 5cm KwK, and its turret was redesigned to accommodate it. The campaigns in France and Poland revealed the need for improved protection, but the basic armor could not be increased. Instead, additional plates were bolted onto the Ausf H’s hull rear, hull front, and superstructure front. The order for the Ausf H was later reduced by 450 units as plans for the new Ausf J model, with heavier basic armor, were developed.
The Ausf H’s turret was newly designed, with its rear formed from a single plate. A new transmission, sprocket, and idler design were also introduced, and an armored cover was fitted to protect the smoke candles. Additionally, the Ausf H was the first model to have a turret basket, which was later retrofitted to the Ausf E, F, and G models. The 30mm + 30mm armor on the front of the hull and superstructure of the Ausf H was impervious at combat ranges to the main enemy tank and anti-tank guns in use in 1941, such as the British 2-pounder, the American 37mm M5, and the Russian 45mm Model 1937.
On June 20, 1941, there were seventeen Panzer divisions on the Russian border, six of which had been issued with PzKpfw 38(t), and eleven had the Pz Kpfw. Every light armored company had a full complement of seventeen PzKpfw III, resulting in a total of 960 PzKpfw III Ausf E to J, including those at detachment and regimental headquarters.