9006 HB4 Premium HID Xenon Kit Wiring Relay Harness Designed to be used with any aftermarket HID KIT using 9006 or even 9005 type factory bulbs Will plug to only 1 side of your vehicle factory bulb connector Connects to your battery, ground, 2 ballasts and one factory bulb connector either 9006 or 9005 Notice vehicles which are very wide may require you to extend 2 wires; (Generally very large trucks only) Basic 9006 Relay