Comparing: VK 30.01 (P) vs. Pz.Kpfw. IV Schmalturm

The Porsche company developed the concept of a new vehicle in 1939. On March 5, 1941, after numerous approvals, the company prepared blueprints and, in July 1941, produced the hull from mild steel. The hull and chassis (with detachable equipment for trenching) passed performance trials. One wooden prototype of the turret and one wooden prototype of the hull were manufactured. In 1942, the project was discontinued in favor of new heavy tanks.

In November 1944 the Krupp company presented several avant-projects aimed to upgrade armament of tanks and tank destroyers in service. Among them there was a project of mounting a Panther's Schmalturm (tight turret) on the Pz IV Ausf. J. The project was canceled due to phasing out the Pz IV production.