Name That Car - Mystery Mercedes-Benz Caught In Orange County

Sometimes the best things simply pass you by.  In this case longtime AutoSpies reader Fred Khaz had this pass him on the highway in Orange County.  Not one to miss a photo op Fred whipped out his camera and started shooting away.

But what is it?  Obviously this is a Mercedes-Benz in testing, but is it a B-Class derivative of some sort or is there too much cammo to tell?

So we ask the best of the best among us.  What is it?

Great Job Fred!  Thanks for The tip!