edal Power® X4 Expander Kit adds four isolated 9V DC outputs to compatible Voodoo Lab® power supplies. Its ultra-compact size makes adding on to your existing system quick and easy, mounting to the even most space-challenged pedalboards. The innovative hybrid DC transformer design of Pedal Power X4 combines exotic components, linear regulation, and computer-optimized filtering to establish industry-leading audiophile quality power that unveils the hidden sonic potential of your rig. SPECIAL NOTE: The X4 Expander Kit requires a 12V DC power source to operate. Compatible power sources include Pedal Power 3 series X-LINK expansion ports or any Pedal Power 12V DC output of 400mA or more. For use as a stand-alone power supply, choose the full version Pedal Power X4