Lepow Official via Amazon offers Prime members the Lepow Impression Series 13,000mAh External Battery Pack in Green for $27.99 with free shipping. (Non-members can spend $35 or more to qualify for free shipping; otherwise, it adds $6.78.) That's $61 off list and tied with last month's mention as the lowest total price we could find. It features microUSB inputs and outputs, smart sleep mode, and four LED battery status indicators. It's compatible with a range of iOS and Android devices.