The power supply unit of the light chain is not officially fully weatherproof and is recommended by the manufacturer for indoor use. Although the power supply unit bears a sticker with "for indoor use only", the print underneath shows IP67 certification, which indicates that it is suitable for outdoor use. Nevertheless, outdoor use is currently considered to be at your own risk and the guarantee or warranty may be invalidated in the event of damage outdoors. The light chain itself is weatherproof and suitable for indoor and outdoor use, but the power supply unit is not explicitly labelled as weatherproof.