Select the voltage for 3 volt, 9 volt, 12 volt etc. it has several adapters for switching polarity and can power up to 500 ma. Great for powering small to mid size keyboards, effects pedals and so much more. Check your items specifications before using. Value Series Multi-Voltage Adapter can be used for almost any
electronic device. It has a switch to change voltage to 3,4,5,6,7.7,9,
or 12 volts and universal plug with four types of adapters w/ polarity
switch 500 mA.