A change in German armored weapons appeared with the arrival of the Russian T-34 tank in 1941. It soon became apparent that the Type III and IV German tanks were inferior in performance to the T-34, which had excellent mobility, armor plate and a powerful 76.2mm main gun. In order to counter this T-34 threat, Germany developed and produced the Type V "Panther" and Type VI "Tiger I" tanks.
The Tiger I was introduced in 1942 and used the powerful 88mm Type 36 L56 main gun against the T-34. Although the Tiger I proved effective, the Russians, upon evaluating the tank, up-graded their T-34 with a much more powerful long barreled 85mm main gun. The hull section greatly resembled the previous Panther tanks, but was much larger in size and weight due to the heavy armor protection. The big difference between the two prototypes was the turret configuration. The Porsche designed turret had a very distinctive shape, with a rounded front section and narrow waist, when compared to the Henschel version. The Porsche turret frontal armor was 100mm thick and 80mm on the side panels, and it mounted the 88mm Type 43 L71 high velocity main gun, capable of penetrating 152mm thick armor plate from a distance of 2,000 meters.
The engine used in this massive tank was the Maybach Type HL230 P30 V-12 cylinder, liquid cooled version of 700 horsepower. The King Tiger, being more heavily armored than the Tiger I, weighed more than 64 tons, and had a maximum speed of 35km/h and a cruising range of approximately 170km. Porsche produced 50 turrets for their version of the King Tiger prior to the official adoption of the Henschel model for mass production. Evaluation revealed that the Porsche turret lacked necessary armor thickness, and required complex tooling due to its rounded contour sculpturing. The 50 completed Porsche turrets were mounted on Henschel chassis' and deployed to the front.
The Porsche turret versions of the King Tiger first saw action in mid 1944 during the Normandy invasion operations and its awesome firepower became well known. Although the King Tiger was an unrivaled weapons system, owing to its advanced technology and sophistication, less than 500 total were produced, including the Henschel versions, and available for combat at any given time.