A Porsche 959 has found its way onto the used car market and what makes it especially unique is the fact that it is a rare and fully functional prototype.

German dealership Mechatronik, which is selling the car, notes that it is one of 12 ‘F-series’ prototypes that were the first development cars built by Porsche, hitting the road before the subsequent ‘V-Series’ and ‘N-Series’ pre-production cars. This 959 was the seventh of the 12 F-Series prototypes built and one of just two painted Ruby Red.

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Porsche originally used this car for testing various electrical systems and hot-weather testing on the U.S. west coast and throughout Europe. The listing notes that most 959 prototypes were destroyed by Porsche but this one survived and returned to Stuttgart where it was re-trimmed and was subsequently purchased by Porsche importer and dealer Vasek Polak. He agreed to never sell, race, or register the car for road use unless it was fully refurbished by Porsche.

The supercar was imported to the U.S. for display purposes and remained there until 1990 when it was shipped to Japan. After Polak died in 1997, his estate sold the car to an individual in Belgium where it remained until 2000 when it was purchased by someone in the United Kingdom.

Just three or four 959 F-Series prototypes are thought to have survived and this is the only running and driving example. This seller notes that it has been driven 26,520 km (16,478 miles) and could very well be the earliest running and driving 959 in existence.