So, you could wire the halos to come on with a set of neons or whatever. But, they light up a hyper blue.The harness is already pre-assembled. All you do is plug your headlight into the harness, and it lights up the projectors and the high beams. However, for the halo ring and the little bulb in the center requires wiring to your parking lamps, so they come on when you parking lights/headlights come on.