This Coiled D-Tap to Z EN-EL15 Dummy Battery Cable allows you to connect a D-Tap power source to a compatible Nikon camera. The cable features a D-Tap connector on one end and a dummy battery that installs into your camera on the other. This cable also features our new Smart D-Tap technology. If everything is plugged in and functioning properly the built-in indicator light will be blue or green. If it isn't, and something is wrong, the light will turn red, indicating an issue. When this happens, power is cut off immediately preventing any damage from occurring to sensitive electronics.