H4 bulbs are dual-filament, meaning they can serve as both high and low beams in a single bulb, commonly used in motorcycles and some older vehicles. In contrast, H11 bulbs are single-filament and typically used exclusively for low beams or fog lights in many modern cars., Informative Read: LED Lights/Bulbs, Projector Vs Reflector Headlights. FAQs: 1. What is H1 H4 H7 bulbs? H1, H4 and H7 are different kinds of automotive headlights, these bulbs have many features and applications. H1 and H7 bulbs are single filament and H4 is dual filament. 2. Is HB3 and H3 the same? No, HB3 and H3 are not the same., Both the H11 and 9006/HB4 bulbs are used for low beam applications, but they throw light a bit differently. The H11 gives you a more controlled light output that helps cut down on glare for oncoming traffic, while the 9006 spreads the light wider, lighting up more of the road., Although the H11 and 9006 (or HB4) bulbs are mainly used for low beams and appear comparable at first glance, these two bulb sizes are not the same. The H11 bulb has a large ring built into its base, whereas the 9006 bulb lacks this feature. Additionally, the pin connectors on the H11 bulb are positioned closer together than those on the 9006 bulb., Single filament bulbs include H7, H11, 9005, and 9006 models. If your vehicle has a dual-beam system, you will probably need a 9003, H4, H13, 9004, or 9007 bulb. The replacement bulb also has to correspond to the socket in your vehicle. Some bulbs have an L-shaped base, while others go straight into the socket., H4, H7, and H11 bulbs are not the same but all belonging to Group 1 lightbulbs per the United Nations’ universal standard for automotive light bulbs. Group 1 means the bulbs can be used for any purpose, but they differ in their filaments, power, and base, so they’re not interchangeable..