Motherboard comes with protection function:
Charging overcharge protection,
over-discharge protection, overcurrent protection.
Intelligent output device after charging full, automatically stop charging, to prevent mobile phones overcharge.
Output voltage and current stable, will not harm user devices.
Micro USB input: 5V 1A
USB Output: 5V 2.1A / 5V 1A(Dual USB interface)
Charging display: intelligent digital display
Batteries Type: liquid lithium-ion batteries (18650)
Product Size: 57mm x 28mm
Screen size:27mm x 17mm
The circuit board is connected to the battery negative B-, B is the positive, do not connecting reversed, connecting reversed will burn the board, the battery is connected