H1 Bulb
A compact single-filament halogen bulb used in headlights and fog lights. Smaller than H7 with a different connector — common in older European and Japanese vehicles.
H1 is one of the oldest standardized halogen headlight bulb types, dating back to European regulations in the 1960s. It's a compact, single-filament design with a P14.5s base — a single-contact bayonet fitting that's smaller and simpler than the H7's PX26d.
You'll find H1 bulbs primarily in high beam positions and fog lights, though some older vehicles use them for low beam as well. Like H7, the standard H1 is a 55W halogen producing around 1,500 lumens.
LED H1 replacements are widely available, and the simpler base design means fewer fitment issues compared to H7. The main challenge is the same as any headlight LED upgrade: ensuring the LED chips are positioned where the halogen filament used to sit, so the reflector or projector can shape the beam correctly. Poorly positioned chips create scattered light that doesn't illuminate the road properly and blinds oncoming traffic.
Specifications
| Type | Single filament |
| Standard wattage | 55W (halogen) |
| Common use | High beam, fog lights |
| Base | P14.5s |
Related Terms
- H7 Bulb
A single-filament halogen headlight bulb commonly used for low beam or high beam in European vehicles. One of the most popular bulbs for LED headlight upgrades.
- H4 Bulb
A dual-filament headlight bulb that handles both low beam and high beam in a single unit. Common in motorcycles, older cars, and many Asian and European vehicles.
- Fog Lights
Low-mounted, wide-beam lights designed to illuminate the road surface in fog, rain, or snow. Positioned below headlights to avoid reflecting off water droplets back at the driver.
- HID Lights (Xenon)
High Intensity Discharge lights that create light by arcing electricity through xenon gas. Brighter and whiter than halogen, but being replaced by LEDs in modern vehicles.
