Amazon.com : GoPro Battery BacPac (Camera Not Included) (GoPro Official Accessory) : Electronics
Expanded Edition BacPac Frame Case For Gopro Hero 3 Hero 3+(Camera+LCD/Battery BacPac ) Mount Accessories - AliExpress
1 Genuine BacPac Frame mount GoPro Hero 3,3+Plus, 4 for LCD or extended battery | eBay
Amazon.com : SOONSUN Frame Mount Extension for GoPro Hero 4 3+ 3 with Screen/Battery Extension - Use with LCD BacPac or Battery Extension - Includes Quick Release Buckle and Thumb Screw : Electronics