#14 is the Multi-Selector for shooting in portrait orientation which makes it much more user friendly than stretching your thumb to reach the standard Multi-selector (5). It can be configured to control only the active AF point or to work the same way as the Multi-selector does. The Sub-selector (2) can be used to move the active AF point and perform like the AE-L, AF-L button on the D3 Series bodies. In other words an addional function has been added to enhance performance and minimize wasted motion. Good Luck and Enjoy your Nikons!