The Synthrotek Power Pak takes the power in your Eurorack case, and converts it to +9V and +12v, and +5V. There are two of each jack, with the barrel jacks having one center negative jack and one center positive jack. With this module, you can easily power guitar pedals, drum machines, controllers, usb lights, charge smart phones, and other devices without having to lug around bulky power bricks of different types. Just plug a male to male connector cable or power train cable into the Power Pak, and you’re good to go! A great tool for live performance as well! By installing one jumper, the Power Pak also allows you to ad +5V to your power distribution board or bus cable which can be used to power other Eurorack modules that need +5V. Save money and space with the Synthrotek Power Pak!