Carl Martin Multi Power Supply Stabilized 9V DC power at any voltage The Carl Martin Powerjack universal power supply for guitar effects employs switch-mode technology, allowing it to be used from 100V-240V The Powerjack delivers 1670mA of stabilized 9V DC power at any voltage The Carl Martin Powerjack universal power supply for guitar effects employs switch-mode technology, allowing it to be used from 100V-240V The Powerjack delivers 1670mA of stabilized 9V DC power at any voltage