The first use needs to be activated by charging with 12V power supply
Without 18650 You need to prepare 3x 18650 batteries yourself to use.
5.5x2.1mm interface input or output functions,with adapter and power switch,weasy to use.
5.5x2.1mm port for 12V LED Light WiFi Router smart Speaker or more devices.
Lithium protection circuit, overcharge, low voltage, overload, short circuit protection
Colour: Black