This will power the Critter and Guitari Pocket Piano, Bolsa Bass, Kaleidoloop, or devices that are 9v DC with a positive center (up to 650mA of current). Standard 2.1mm barrel connector.
This power supply has a standard US plug but operates on any voltage between 100v-240v AC so it can be used worldwide.
The symbol for a 'center positive tip' looks like this:
