... Port 3. 4 Voltage adjustable 4. CE, FCC and Rohs EGO VV passthrough ego usb battery variable voltage EGO VV passthrough variable voltage for electronic cigarette, ... times pressing button will change the voltage, fast and simple;3. compatible with all Ego/510 threads (plus for difference ... from Smaild, smart design, and longworking time, support various voltage.Any question pls fell free to ask me, I ...