This is a supermini USB soldering iron. It is power via the USB interface, so you can power it by power bank, portable power source, USB adapter, and so on.
Slightly touching the metal point on the body of the soldering iron, the LED will be lightened up and can be started to working. If leaving it unused for 25 seconds, the LED light will be turned off and the iron will get into sleeping mode automatically.
Note: Do not rotate when removing the iron head cap, just pull it out, otherwise, the soldering iron head will not be hot or the heat does not last when it is loose. Be sure to keep the nut on the iron head in a tightened state!