Relays are a required item whenever you want to use your XFI ECU to control a high-current device, such as a fuel pump or nitrous solenoid with one of its low-current outputs. FAST offers relays to cover many applications. When choosing a relay, it's very important that the relay current rating (shown in amps) be appropriate to the current requirements of the device you intend to control with it. So, if you're in need of a relay--think FAST relays.