The Ferrari Berlinetta Boxer prototype was a concept vehicle unveiled at the 1971 Turin Motor Show. It represented Ferrari’s first mid-engined twelve-cylinder road car design study and served as a direct precursor to the production 365 GT4 BB introduced in 1973. The prototype was constructed by Pininfarina and designed under the direction of Leonardo Fioravanti. It was conceived to evaluate the integration of a horizontally opposed twelve-cylinder engine in a grand touring configuration. The vehicle was built on a tubular steel chassis incorporating a semi-monocoque central structure. The engine was a flat-twelve (Tipo F102A), positioned longitudinally behind the cockpit. Displacement was 4,390 cubic centimetres. The engine featured twin overhead camshafts per bank and was fed by six Weber carburettors. Output was approximately 360 metric horsepower. Power was transmitted to the rear wheels via a five-speed manual transaxle. Suspension was independent on all four wheels with unequal-length wishbones and coil springs. Braking was by four-wheel ventilated discs. The exterior styling was characterized by a wedge-shaped silhouette, integrated rear buttresses, concealed headlamps, and a full-width rear fascia. A distinguishing horizontal black band running below the beltline visually reduced the vehicle’s height and became a signature element in the subsequent production series. The body was executed in steel and aluminium and featured a mid-rear longitudinal engine configuration, marking a departure from Ferrari’s previous front-engined V12 models. Only one example of the 1971 Berlinetta Boxer prototype was constructed. No public record of a chassis number has been released, and the vehicle remained within Pininfarina’s custody for evaluation and presentation purposes. It was not offered for sale, and no subsequent ownership changes have been documented. The prototype marked a significant transition in Ferrari’s road car development, influencing the design and engineering of the 365 GT4 BB and its successors, the 512 BB and 512 BBi. It signaled the company’s commitment to mid-engine architecture for high-performance grand touring vehicles. The Berlinetta Boxer prototype remains a key reference in Ferrari’s design evolution and in the broader history of mid-engine GT car development. Its current status and location are not publicly confirmed.