This VVPS requires a separate power supply to feed it power, sold separately, and can only lower the voltage, not raise it higher than the power supply can provide. You will need a 12 or 15 volt power supply with a center-positive 2.1mm barrel plug and DC (not AC) voltage. Using a power supply that puts out more than 15v will immediately damage your VVPS. If you have any doubts about your set up, please contact us first.
VVPS does include (2) three-foot extension cords, so that you have a spare. This VVPS is just called "Travel" because it's so small, but you can use it wherever and whenever you like. If you prefer the knob on the left hand side, let us know in your order comments and we'll try to accommodate.
Please read our voltage guide as fire, or damage to your vape, can occur when using more than 12v.