RCA and Clip cords are the highways that connect the electric circuitry that powers your machine from your power supply. RCA cords are standard issue, same as the ones you might use on your TV’s. They are less likely to lose connection than the old clip, because it inserts directly into the plug. The Clip cord is the old school clips that connect to the frame and back binding post of your coil tattoo machine. This type of connector would be the default if you were using old school machines.