Trumpeter 1/35 German NBFZ (Type 1) Heavy Tank Scaled Plastic Model Kit

Development of the Neubaufahrzeug (German for "new construction vehicle") started in 1933 when the Reichswehr gave a contract for the development of a heavy tank (codenamed Grosstractor) to both Rheinmetall and Krupp — Germany was still forbidden to develop tanks under the Treaty of Versailles.

The two designs resembled each other closely, the main difference being weapons placement. Each had a main turret armed with a 75 mm KwK L/24 main gun and a secondary 37 mm KwK L/45. Rheinmetall's design mounted the second gun above the 75 mm, while the Krupp design had it mounted alongside. Both designs had a secondary turret at the front and rear of the main turret, using slightly adapted Panzer I turrets with standard machinegun armament.

Rheinmetall's design was designated the PzKpfw NbFz V (PanzerKampfwagen NeubauFahrzeug V) and the Krupp design the PzKpfw NbFz VI. The design proved too complex and unreliable for a frontline heavy tank role, but development continued to give the nascent German military experience with multi-turreted tanks.