Charges and provides extra backup power for 18650 size batteries only. Will not charge CR123a size batteries.  Carry multiple batteries with you to get virtually unlimited backup power on the go. Charge port on-board -- charge up your backup batteries from an USB port without carrying a separate charger.

Specifications:

• Will charge rechargeable Li-ion 18650, 18500 batteries.
• Input: 5-12V DC
• Output: 4.2V/1.5V 1A DC
• Discharge: 5V/1A
• Battery NOT included as shown in photo.