Artist's view!
Conversion based on Einheitfahrgestell III/IV mixed chassis. First baptized leichte Panzerjäger III/IV, by order of Hitler, this tank destroyer will be renamed Panzer IV lang (E) or Panzer IV / 70 (E) (E for Einheitfahrgestell).
However, the program is stillborn, Germany having decided to keep only the tracked platforms based on the Panzer 38 (t), Panther and Tiger II chassis in production for 1945 ... pending standardized chassis of the Entwicklungsserie (E-Serie).