This is the brightest headlight bulb you can reasonably use, and it will dramatically
improve your vision. However, due to the increased current draw, you will generally need a Relay to use this bulb without damaging your headlight switch. We sell this
kit for use on '80-85 Vanagons, which includes everything you need as well as simple instructions. There is info on the internet for adding relays to other vehicles. We also recommend that you check and clean all headlight grounds when using uprated bulbs. When installing an H4 bulb, you must not touch the bulb (only the base), as the oil from your fingers will cause the bulb to fail; therefore we do not warranty bulbs. Not recommended for vehicles with plastic headlight lenses.