The Pep 4,000 mAh Power Bank is a lightweight rechargeable lithium polymer Grade A battery device powerful enough to charge smartphones, MP3 players and more. This reusable power bank charges via a USB cable (included) which can recharge the battery backup or be used to charge up devices with a micro-USB input like Android smartphones from Samsung, Motorola, HTC, Nokia, and others. Input: 5V 1000mA. Output: 5V 1000mA.