The Panzer IV was the most widely manufactured German Tank and the second-most widely manufactured German armored fighting vehicle of WW II with some 8,500 built. The Panzer IV chassis was used as the base for many other fighting vehicles, including the Stug IV assault gun, Jagdpanzer IV tank destroyer, the Wirbelwind self-propelled AA Gun and the Brummbar assault vehicle.
The Ausf H was introduced in May 1943 and production continued into mid 1944.The tanks frontal armour was increased to 80mm and a new transmission introduced along with a new pattern rear idler. Over 3500 vehicles were produced.