These units don't come with external power supplies.

This Pivitec e32 Personal Mixer set includes 3 mixers and an eRack Kit but no power supply. To use it, you'll need to provide your own suitable power source. When using, make sure to place it on a stable surface. Avoid using it in wet or dusty environments. After use, turn it off properly. For maintenance, keep it clean with a dry cloth. Don't try to open the device on your own as it may void the warranty.