Panzerkampfwagen VIII Maus (English: 'mouse') was a German World War II super-heavy tank completed in July of 1944.

The 128 mm gun was powerful enough to destroy all Allied armored fighting vehicles in service at the time, with some at ranges exceeding 3,500 m (3,800 yd).

[4] The principal problem in the design of the Maus was developing an engine and drivetrain powerful enough to adequately propel the tank, yet small enough to fit inside it – as it was meant to use the same sort of "hybrid drive", using an internal-combustion engine to operate an electric generator to power its tracks with electric motor units, much as its Porsche-designed predecessors, the VK 30.01 (P), VK 45.01 (P), and Elefant had.

This was reportedly changed to Mäuschen ('little mouse') in December 1942 and finally to Maus ('mouse') in February 1943, which became the most common name for this tank.

Each 1.1-meter-wide track, which used the same basic "contact shoe" and "connector link" design format as the Henschel-built Tiger II, was driven by its own electric motor mounted within the upper rear area of each hull side.

The gun mantlet was 250 mm (9.8 in), and combined with the turret armor behind, the protection level at that section was even higher.

The 128 mm PaK 44 anti-tank field artillery piece of 1943 that Krupp adapted for arming the Maus as the Kampfwagenkanone (KwK) 44 retained, in parallel to the Porsche project, its original anti-tank Panzerabwehrkanone family designation of PaK 44 when mounted in the casemate-style Jagdtiger tank destroyer.

By May 1943, a wooden mockup of the final Maus configuration was ready and presented to Hitler, who approved it for mass production, ordering a first series of 150.

In his book Panzer Leader, Heinz Guderian wrote: On 1 May a wooden model of the "Maus", a tank project of Porsche and Krupp, was shown to Hitler.

Future planned modifications included provisions for a MG 151/20 cannon for anti-aircraft defense mounted in the turret roof.

Due to its size, it could ford relatively deep streams, but for deeper ones it was to submerge and drive across the river bottom.

Meanwhile, the V2 prototype started tests in September 1944, fitted with a Daimler-Benz MB 517 diesel engine,[9] new electric steering system and a Skoda Works-designed running gear and tracks.

After the war, the commander of Soviet armored and mechanized troops ordered the hull of V1 to be mated with the turret of V2.