With battery packs, there are plenty of options available. Though the normal size of the external charger is around 5,000 mAh, some prefer a larger pack. With the TYLT Energi 10K, you’ll get 10,400 mAh of battery in a stylish, sleek package. Slick styling doesn’t tell the whole story, though. We put the 10K to the test to see if it holds up to another TYLT pack we highly recommend, the Energi+.