newegg offers the RAVPower 14,000mAh External Backup Battery Pack, model no. RP-PB13, for $34.99 with free shipping. That's the lowest total price we could find by $8 and a very low price for a 14,000mAh or greater backup battery. It features a built-in flashlight, auto-off, and compatibility with a wide range of devices (including the iPad, iPhone, and Android phones).