The Surface tablet line set out its basic design rules with the very first generation of products and has largely stuck to its guns since. What we've seen, instead of wholesale reimagining, is a steady march of improvements to the display and chassis, helping the product feel just a bit more premium with every generation.
The earliest Surface Pro models were 13mm thick, while last year's Surface Pro 3 shaved that down to 9.1mm. This year, we're down to 8.4mm, despite increasing the size of the screen. Both the Surface Pro 3 and Surface Pro 4 are 1.7 pounds (771 grams) by themselves, or 2.5 pounds (1.13 kg) with their keyboard cover and stylus pens attached.
One of the biggest improvements to last year's Surface Pro carries over here: the highly adjustable kickstand, which can be adjusted to nearly any angle between 22 and 150 degrees. The kickstand, which runs the entire width of the system, is stiff enough that it will stay where you put it, and hardly moves at all, even when using your fingers or the pen on the touchscreen.
Missing from the black bezel surrounding the screen this time around is the capacitive Windows logo touch button. In previous Surface models, this moved around from the long edge to the short edge of the system, but always served the same purpose: to take you back to the Windows 8 tile interface. As we're now operating in the Windows 10 world, having a physical home button isn't necessary, although the Windows 10 "tablet mode" is still very similar to what Window 8 looked like.