This is a wall charger with a USB port and a battery slot. We can insert the battery to the slot, and plug charger to the wall socket. It begins charging the battery. Meanwhile, we can plug our mobile phone to the USB port under the wall charger. So, it is very convenient, supports charge battery and phone together or separately.

100% brand new, high quality
Phone and backup battery charging simultaneous easily.
Charging stop once battery is full.
Never overcharge keeps the performance and life of the battery.
More convenience to interchange your standby batteries.
Input:Ac 100-240V~50/60Hz 0.15A
Output:Dc 4.2V~350mA~±50mA
USB 5.2Vd.c.800mA

Weight: 60g
Package includes:

1× US AC USB Phone + Battery Wall Charger Adapter
Australia buyer will get a extra AU adapter
europe buyer will get a extra EU adapter