Infapower’s 4 Channel USB Charger has the following features.

Charges 1, 2, 3 or 4 batteries at a time  
Charges any brand of rechargeable batteries  
Charges using Micro USB cable (included)  
LEDs show which batteries are being charged  
Worldwide use with USB plug (not included)  
Short circuit protection  
Compact and light  
Reverse polarity and bad cell detection  

4 Channel USB Charger

Hover over image for Inner and Outer quantities.

Inner 6 / Outer 36