Comparing: Panther/M10 vs. E 25 vs. Pz.Kpfw. IV Schmalturm

During the preparation of Otto Skorzeny's Panzerbrigade 150 for the Ardennes offensive, four Panther tanks were disguised as M10 tank destroyers. The tank brigade was to carry out diversions deep behind the allied lines. All vehicles were lost during the battle with the 120th U.S. Infantry Regiment on February 21, 1945.

The development of the E 25 was part of the "E" program, supervised by the Waffenprüfamt 6 committee. The E 25 was developed by the Argus company (Karlsruhe, Germany) under the supervision of Dr. Herman Klaue. No prototypes were manufactured.

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.