Microsoft watchers know that the word Signature is assigned only to devices and products that have Redmond's wholehearted approval. In the past, this meant PCs, tablets and 2-in-1s which run bloatware-free versions of WIndows and that offer a unique value in terms of features and design.
It seems the Signature series is evolving to accessories as well with the new Signature Type Cover, which blends high-technology and fashion into one intriguing and exciting new Type Cover for the Surface Pro 3 and Surface Pro 4 lines. Made from a luxurious fabric called Alcantara, the Type Cover costs more than your run of the mill Type Cover but stands out in terms of look and feel for those who pay attention to these sort of things.
Alcanatar apparently, "ages beautifully, growing richer and darker over time, and is wonderfully soft to touch," the company added. That speckled gray color "pairs perfectly" with your Surface device.