Extended Battery BacPac Kit for GoPro HERO4 Hero 3+ Hero 3 Action Cameras with Waterproof Back Door and USB Charger Cord Replacement for GoPro Battery Back Pack ABPAK-304 BacPac Battery attaches to your GoPro HERO4, HERO 3+, HERO 3 camera to double battery capacity NOTE:This BacPac Door is compatible with Gopro Hero 3+ and Gopro Hero 4 only, NOT Gopro Hero 3 Easy to plug into any USB charging source(PC, wall, auto charger) Displays the charge and record activity with LED light & the battery level and charge status in LCD window Ideal for long-duration Time Lapse photo sessions, endurance motorsports racing or any application where you need extended battery life