H4 Bulb Explained

H4 Bulb Explained

by Nathan Reeves on February 01, 2022 Categories: Xenons Online Blog

Most people do not know the difference between the many kinds of headlight bulbs, this can make it difficult when looking to buy bulbs for your vehicle. Knowing more about headlight bulbs will help out in future when shopping for the best bulbs for your car.

H4 Bulb

In this post we will cover what's different with the H4 Bulb and how it is used.

The H4 bulb is one of the larger bulbs out of the different bulb types available, this is due to the H4 Bulb having two filaments. One for Dipped Beam and another for High beam. Because of this the headlight itself only requires one bulb for both the Dipped Beam and Main Beam, where as other headlight using a H7 Dipped Beam for example would also require a second bulb such as a H1 to take care of the Main Beam.

The easiest way to determine if your bulb is a H4 Bulb is to look at the back of the bulb, this can be done without removing the bulb. If it is a H4 Bulb then it will have 3 pins, one pin for neutral / earth and two Live pins for Dipped and Main Beam.  

H4 Halogen Bulbs

H4 Halogen Bulb

A standard H4 bulb will be halogen, halogen bulbs are generally produce low amounts of yellow coloured light. The exception to this is our H4 Halogen Performance Range, being filled with xenon gas and coating the glass we are able to produce a much brighter white halogen bulb.

H4 Xenon Bulbs

H4 Bi Xenon

Xenon Bulbs require an additional ballast to power the h4 bulb, so this isn't a direct replacement. If you already have a H4 Xenon Bulb installed with the Ballast then our H4 Xenon Bulbs are the ideal replacement. If you are looking to upgrade your Halogen H4 to Xenon then you would need to purchase a H4 Xenon HID Conversion Kit instead.

H4 LED Bulbs

H4 LED Bulb

H4 LED bulbs produce as much light if not more than the Xenon Bulbs. They also do not require a ballast to control them meaning a quicker and easier install all round. The H4 LED Bulbs produce a brilliant bright white light, transforming the look of your headlights to a more modern stylish look, with the added benefits of more visibility.