Voodoo Lab Cable 2,1 mm voltage doubler

Some pedals use higher voltage than normal 9 volts. With this cable you can combine two outputs from your power supply. This way you can double the voltage to suit pedal requirements. Combine two 9 volt outputs for 18 volts, Combine two 12 volt outputs for 24 volts, 2,1 mm adapter, Normal polarity, center negative.