Last we saw the SLK with a glass retractable roof was during winter testing earlier this year. Now the prototypes are back, this time hot weather testing in the American desert. These photos for the first time show a tiny view through the top glass roof panel, giving some perspective as to it's panoramic effect.
Judging by the black tape along the sides of the trunk lid, it's safe to say that the lid has been restyled to accommodate the new roof.
We're expecting to see this sleek retractable glass roof on SLK's for the 2010 model year.
