Heavily influenced by the Ferrari 250 - P5, the Pininfarina Alfa Romeo coupé prototype, on a Type 33 sports car chassis, in contrast to the Ferrari P6 which resulted in the BB (Boxer Berlinetta), returned to the concept of a concave front, ovoid rear wings, "gull-wing" doors and the transparent roof going right to the back of the car. The engine, as on the P5/6 prototype, is mounted in the middle of the car.