PNY M3000 External Battery Rechargeable 3000 mAh Micro USB cable Black (Accessory)
Tested with a Sony Z1 experia fully discharged: After connecting the M3000 and after a few hours, the Z1 has drained backup battery charge and ended up at 60%, an autonomy of slightly more than half -day in my case. The M3000 is very compact, and onc