of Pininfarina. The Ferrari 550 Barchetta Pininfarina was a true barchetta with no real convertible top provided. The factory did provide a cloth soft top, but it was intended only for temporary use to protect the interior from rain as using the top above was not deemed safe. Aesthetically, the barchetta featured a more deeply raked windshield than the coupé for improved aero dynamics, roll-over hoops behind the seats for the driver's safety and a longer rear section than the coupé to complete the smooth overall design resulting in more cargo space than the coupé, even when it was less practical. Other changes included new 19-inch alloy wheels specially made for the barchetta. A total of 448 cars were produced, four more than initially planned 444 cars due to concerns of superstition in the Japanese market about the number 4. The 448 cars were preceded by 12 prototypes numbered P01–P12 on their interior plaques. To an observer the prototypes and production cars are indistinguishable. The mechanical underpinnings of the car remained the same as its coupé counterpart but the engine was given the F133C code mainly for differentiation. Performance figures differed as compared to the 550 Maranello due to the loss of a roof, with acceleration time same as the coupe at 4.4 seconds but top speed reduced to . All the 448 cars had a numbered plaque (i.e. x of 448) on the dashboard with Sergio Pininfarina's signature. Concept cars and one-off specials Rossa The 550-based Ferrari Rossa was a concept car introduced at the 2000 Turin Motor Show to celebrate the 70th anniversary of Pininfarina. The 2-door speedster shares the mechanical components from the 550 Maranello but its top speed is reduced to due to increased weight. The futuristic design cues found their way to future Ferrari production cars such as the Enzo Ferrari and the F430. It was designed by Ken Okuyama at Pininfarina. 550 GTZ Barchetta On October 28, 2009, Zagato and Ferrari revealed that they have been working on a roadster version of the 575 GTZ coupé to celebrate the 90th anniversary of the long collaboration between the two Italian establishments. The resulting product called the 550 GTZ Barchetta was limited to only three units and based on the 550 Barchetta Pininfarina, including one RHD example. Unlike the original version, Zagato developed an electronically-operated roof. All were sold at a price of £1 million (€1.1