The Nikon SC-29 Cord is dimensionally different than previous Nikon flash cables. Thus, it is not readily compatible with Wimberley brackets or many other flash brackets on the market.
The FA-11 attaches to the bottom of the Nikon SC-29 cord, making it compatible with Wimberley, Really Right Stuff, and Kirk Flash brackets.
Once the FA-11 is installed, you can attach your SC-29 cord to Wimberley flash brackets just as you would with older Nikon cords. You can leave the FA-11 permanently attached to the SC-29 cord.