if you hire your Go Pro hero 4 black edition camera from us then it already comes supplied with one GoPro Battery backPac to extend the battery life by approx 2x. For even longer running times or for convenience on a trip then we recommend you rent a second GoPro BackPac, as a great accessory to double the life of your batteries. Giving you more time recording and less time charging. For long trips and long scenes, the more battery life the better. This battery also works on the Gopro Hero3.
You can charge your camera and backPac battery while still using the camera - without the battery BackPac when you charge the camera you cannot use it so the backPac is useful on extended trips or for tethered operation of the GoPro 4 itself.
The battery backPac can be charged independently of the camera via a mini USB cable and features a side button with indicator of battery life. Use the battery backpack in place of the GoPro LCD screen. This battery comes on its own in a small Go Pro box. If you need the extra housing back door and usb charging cable