H4 Headlight Bulbs

An H4 bulb is a dual-filament headlight bulb with a P43t base: two filaments in one capsule, so a single bulb provides both low and high beam. In this section you’ll find H4 halogen bulbs from Osram and Philips for 12 V and 24 V, as well as Niken H4 LED bulb kits (2 bulbs per set) with built-in drivers.

How do you know your car needs an H4 bulb?

The easiest way is to check the marking on the base of the old bulb or in your car’s manual. An H4 bulb has three contacts and a metal flange with three tabs; in the headlight it handles both low and high beam. If your headlight uses two separate bulbs for low and high beam, it has different bases, most commonly H7 or H1, and an H4 won’t fit. Fog lights usually have their own base, so you need to check that separately. Model year or VIN may not be enough for selection: the same model can come with different headlight assemblies.

Halogen or LED H4: which to choose?

A halogen bulb is the OEM solution for H4 headlights: it installs with no modifications, gives a warm light, and is typically sold individually. Niken LED bulbs shine whiter (6500 K) and consume less power, but they have a heat sink or a fan, so before buying make sure there’s enough space under the headlight dust cover. On cars with bulb-out monitoring, you may need a CANbus adapter, and for a secure fit in the mounting seat you may need a mounting adapter. Rules for installing LEDs in halogen headlights vary by country, so check local regulations before upgrading.

12 V or 24 V: H4 bulbs for cars and trucks

Passenger cars run on a 12 V electrical system, while trucks and buses use 24 V. For 24 V you’ll find Osram 64196 and Philips 13342 halogen bulbs rated at 75/70 W, plus the Niken Pro-series LED in a 24V version. Bulbs for different voltages are not interchangeable: a 12 V bulb in a 24 V system will burn out quickly, and a 24 V bulb in a car will be noticeably dim.

Other automotive bulbs

LED bulbs with other bases are collected in the LED bulbs section, and xenon bulbs in the xenon bulbs section. All bases, adapters, and auxiliary bulbs are in automotive bulbs. If you need new optics, take a look at headlights.

This description was prepared with AI based on an analysis of over 1 million phone calls between DD Tuning sales managers and customers, as well as the company knowledge base. We collected the questions customers ask most often and the answers verified in real-world use.