Anker 321 Power Bank (PowerCore 5K) is a 5,200mAh Portable Charger that is lightweight and super compact and capable of charging 2 devices at once. It is the size of a small candy bar (3.8 × 1.7 × 0.9 in, 4.2 oz) so it fits perfectly in your pocket. Exclusive PowerIQ technology detects your device to deliver its fastest possible charge speed up to 2 amps (four times faster than a standard computer USB port).