 No production beyond the prototype was reported.During the Second World War, Ferdinand Porsche sought to use his firm's experience in hybrid drivetrain design for powering armored fighting vehicles for Nazi Germany.A series of designs, starting with the VK 3001 (P), the unsuccessful VK 4501 (P) heavy tank prototype (which became the "Elefant" tank destroyer) and concluding with the heaviest armored fighting vehicle ever prototyped, the Panzerkampfwagen "Maus" of nearly 190 tonnes in weight, were just two examples of a number of planned Wehrmacht "weapons systems" (including the highly-"electrified" subsystems on the Fw 191 bomber project), crippled in their development by the then-substandard supplies of electrical-grade copper, required for the electric final drives on Porsche's armored fighting vehicle powertrain designs.