Noctua looked at their previous high-end tower heatsink and beefed it up to match it up to larger fans. The NH-D14 will easily fit up to 3x140mm fans, although the third fan you'll need to find your own clip-on gear as the D14 comes with clips for max 2 fans (sized up for 120mm mounting holes). The heatsink with all the standard fans installed is quite intimidating and much larger than most mainstream tower heatsink we've tested in the past.
You can see a total of 6 U-shaped heatpipes and the base already has two mounting screws pre-attached. Other thing of note is the connector for the fans, each one 3-pin. Next to the heatsink you'll also find the following goodies inside the box:
Three bags, one for AMD-only platforms, the other Intel-only platforms, a common parts bag, which also includes thermal paste, the Ultra-Low-Noise adapter and a Y-splitter for two 3-pin stock fans. A metal phillips head screwdriver is included if you don't have a long screwdriver lying around... luckily we have such a tool and did not have to use the Noctua provided tool, it's there if you need it. The manual is very clear for all installation steps and comes with good illustrations.
A closer look at the heatsink without the fans reveals pre-installed anti-vibration strips for both fan-mounting positions. In the middle picture you can see the identical size of both towers.
Other areas of note is the smooth nickel plated copper base and the custom fan mounting brackets which rely on a small plastic insert to fix the fan in place. This also implies that only "open-flanged" fans can be installed with the provided clips.