Dry-Ionic, used item. Power is supplied via an AC adapter (operation confirmed). The adapter is small and removable, so it can all be stored in the main unit box when not in use. I think this is a compact specification that you probably won't find elsewhere. [Included Items] AC adapter: 2 Glass fuses: 4 (including 2 spares) Spare power connectors: 2 Electrode cleaning sandpaper: Several sheets Contact-easing felt: Several sheets