The next generation of the SLK roadster (on sale next year) is to be fitted with a glass roof which Mercedes-Benz will offer with a 'panoramic vario-roof' - aka Magic Sky Control. Being transparent, it provides that open-air feeling even in poor weather, yet it can be darkened on demand in a matter of seconds thanks to some sort of electrically-susceptible foil.
"As such, by optionally affording shade and a unique ambience, it helps to ensure a pleasant wellness atmosphere in the interior," says the press release, and who are we to argue?
According to the release which accompanied these images, with an open roof, the sun load in the heat of Death Valley testing reached 1000 to 1100W per square metre. With the transparent glass roof it dropped to 200W, and when the roof was switched to darkened mode, it dropped to 40 to 50W - just one 20th of the original value.