@Dennis Rockholt The basic premise of a retrofit is to take apart your headlights and rebuild them with an HID projector inside. Projectors give you an advantage since they're more capable of focusing the extra intensity from HID lights onto the road much more effectively than the stock halogen reflectors can. Basically all the light ends up on the road where you want it; giving you better visibility and reducing glare to oncoming traffic. Adding HID's to reflectors will make the lights brighter, but since it's not as focused - you're not getting the full advantage.