Sturmgeschütz neuer Art mit 7.5 cm PaK L/48 auf Fahrgestell Panzerkampfwagen IV (SdKfz 162): Specifications originated in 1942 calling for a heavy assault gun with 100 mm armor. A wooden model, made by Vomag Betriebs of Plauen/Vogtland, was shown to Hitler on May 14, 1943 and a soft steel model was presented to Hitler in October 1943. The final prototype was made in December 1943. Jagdpanzer IV/70(V): Built by Vomag. A prototype with the longer L/70 gun was introduced in May 1944. The gun was made by Gustloff of Weimar and Skoda. .