Comparing: E 25 vs. ISU-122S

Development of the E 25 was a part of the "E" program, aimed at unifying the manufacture of the German armored forces. The program was supervised by the Waffenprüfamt 6 committee, directed by General Kniepkamp. The E 25 was developed by the Argus company (Karlsruhe, Germany). No prototypes were manufactured, the vehicle never underwent trials or saw service. However, according to some sources, by January 23, 1945, several hulls were produced and remained in Katowice waiting for trials.

A heavy assault gun, built on the basis of the IS tank, was effective against German heavy tanks as well as fortifications. The prototype was built at the Chelyabinsk Kirov Plant in April 1944. The vehicle entered service in August of that year, and a total of 675 vehicles were manufactured in 1944 and 1945.