Don't let a burnt out bulb limit your vision at night. This D3S gas discharge replacement bulb will get your exterior lights lit up properly, so you can see and be seen while driving in the dark. Gas discharge bulbs make more visible light, in contrast to heat, when compare to their halogen counterparts. This bulb does not include the ballast. Bulbs are recommended to be replaced in pairs, as it is common when one bulb burns out, the other is not far behind. Be sure to take a look at all of your lights to be sure no other bulbs need replacing. Xenon bulbs cannot be used in place of halogen bulbs without modification or conversion.