It is vital that you order and use the correct power supply to avoid inconvenience or damage your product. Polarity, voltage, AC/DC and DC plug type vary between models. You should only use an original PSU supplied by DrayTek; The usage of any unapproved 3rd party power supply which has not undergone our rigourous safety and operational testing and will invalidate your warranty and may permanently damage your product. . When selecting your PSU, refer to the actual product itself, not the original PSU, the box, invoice or other documentation. The replacement PSU you receive may differ in appearance to the original but if you have ordered the correct model, it will be compatible/suitable - please check if in any doubt.