Mercedes-Benz 300 SLR
Daimler-Benz developed this hardtop version of the 300 SLR racing car for the 1956 season. It was never used in racing, however, because the company ceased its motorsport activities at the end of the 1955 season. Instead, the 300 SLR coupe served the head of the Test Department, Rudolf Uhlenhaut, as a company car.
Source: Mercedes-Benz press