Due to the overwhelming popularity of the Cellink Battery B battery pack, we've brought in the expansion pack accessory from the folks at EGEN. The expansion pack simply connects to the main battery pack and essentially doubles the total capacity, matching the main pack's 6000 mAH.
Additionally the expansion pack provides two USB ports which can be used to charge a smartphone or other USB accessory. If unplugged from the main battery pack, the expansion pack can be used as a USB/12v power supply unit which might come in handy for camping etc.
To purchase the Cellink expansion pack, simply click the drop down menu on the Cellink Battery B product page and choose the appropriate option!