The original is lost, so Mercedes built a new one.
Silver Arrows is the nickname the current Mercedes GP/AMG Petronas F1 team is known by, but the name has a long and storied history. The Silver Arrows moniker was originally given to the Mercedes-Benz and Auto Union race cars that dominated Grand Prix racing between 1934 and 1939. The name comes from a radio broadcast where the 1932 Mercedes-Benz SSKL (Super Sport Short Light) was described as a silver arrow, but the reason the cars were silver is a matter of debatable folklore. The reason this one was unpainted is simply because the team didn't have time to paint it before the race.
Mercedes pulled out of racing in 1931 and the 1932 streamlined car was debuted by Manfred von Brauchitsch at the Avus race that year. Since then though, the car has been lost to history. The significance of the car is immense and was a sign of what was to come in race car technology and, specifically, aerodynamics. Mercedes has taken a leaf out of other manufacturers' books and built a replica that will get its first public outing on the road at Pebble Beach this year.
This early example of improved aerodynamic design was developed by Baron Reinhard von Koenig-Fachsenfeld and reduced drag by 25% to allow the car to reach a top speed of 146 mph. That was a full 13 mph faster than SSKLs fitted with the regular body. Drivers didn't call it the Silver Arrow though, they stuck with 'Cucumber'.
Aerodynamics weren't the only weapon the 1932 SSKL had at its disposal. It weighed around 275 pounds lighter than the SSK model due to techniques used that included drilling holes in the frame. Then there was the power plant. That was a 7-liter straight-6 engine making 237 horsepower until it had a supercharger attached to bring it up to 296 hp.
As there is no car to measure up and copy, Mercedes had to build the replica using documents and photos from the archive and the detail goes all the way down to those holes in the frame. The car debuted at the Goodwood Festival Of Speed, but we'll see it drive for the first time at the 2019 Pebble Beach Tour d'Elegance before it goes on display at the Mercedes-Benz Star Lounge.