四号一直都在有研究，也一直都在生产
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# Ausf. F1 (1941-1942, 462 produced): Simplified construction.
# Ausf. F2 (1942, 175 produced): Armed with a new, longer-barreled 7.5 cm KwK 40 L/43 gun.
# Ausf. G (1942-1943, 1687 produced): Thicker turret armor, winter combat modifications. Some late Ausf. Gs were fitted with 'Schürzen', side skirts, thin metal plates attached to the hull sides and turret via mounting brackets for protection against Soviet anti-tank rifles as well as hollow-charge rounds.
# Ausf. H (1943-1944, 3774 produced): Longer 7.5 cm KwK 40 L/48 gun and thicker armor. Radio antenna moved to left rear of hull.
# Ausf. J (1944-1945, 1758 produced): Turret traverse engine replaced with an extra fuel tank. Later ausf Js had simplified vertical exhaust mufflers and the use of 3 instead of 4 track return rollers. Very late ausf J's used wire mesh side-skirts (Drahtgeflecht Schürzen) in place of solid metal plates to conserve strategic materials and reduce overall weight.
