H11A vs H11B / H7A vs H7B HID bulbs
When choosing an HID conversion bulb, the base size is only part of the story. H11A, H11B, H7A, and H7B refer to different return-wire orientations. Choosing the wrong version can place the return wire in the beam path and create a shadow, dark spot, or reduced usable output.
Shopping for an LED upgrade? LED forward-lighting bulbs are fully clockable - you rotate them after installation to adjust beam position. They have no return wire, so H11A vs H11B and H7A vs H7B do not apply to LED bulbs. If you're installing an LED headlight or fog light bulb, you do not need this guide. Shop LED headlight & fog light bulbs →
Quick answer: Pick the version that keeps the HID return wire pointing down once the bulb is locked into the headlight. That keeps the wire out of the main optical path and helps prevent a ground shadow, which looks like a dark band through the beam.
H11 rule of thumb: H11B is the most common H11 HID conversion bulb. If the original H11 halogen bulb locks in facing downward, the HID conversion is usually H11B. H11A is much less common and is mainly used when the bulb locks in facing upward or the vehicle needs the opposite return-wire orientation.
Important: Do not rely only on a generic chart. Remove the original bulb and check the tab orientation before ordering. Many vehicles have package differences, aftermarket housings, or previous repairs that change what is actually installed.
HID bulbs have a return wire
Halogen bulbs do not have the same outside return wire. HID capsules do. If that wire sits in the wrong place, it can block or scatter part of the beam.
Wrong orientation can create shadows
A misplaced return wire can cause a dark line, uneven hotspot, or reduced output, especially in projector housings where beam control is more precise.
Match the bulb to the housing
The correct A or B version helps position the return wire where it interferes the least with the reflector or projector optics.
H11A vs H11B
In HID conversion kits, H11A and H11B describe opposite return-wire orientations for H11-style HID bulbs. H11B has the return wire positioned at the bottom of the bulb, and H11A uses the opposite orientation.
Once installed, the return wire should point downward in the headlight. If the wire ends up across the hotspot or cutoff, it can create a ground shadow, dark band, or uneven beam pattern.
This is different from the OEM H11B halogen plug used on some Hyundai and Kia vehicles. H11B is still the most common H11 HID choice, but a few applications can use an H11B halogen bulb and still need an H11A HID bulb for the correct installed wire direction.
H7A vs H7B
H7 HID bulbs also use A and B versions to change the return-wire position:
- H7A: The return wire is positioned opposite the alignment tab (180° away from the tab).
- H7B: The return wire is positioned on the same side as the alignment tab.
The goal is the same as H11: install so the return wire points downward once the bulb is locked in. Remove the original H7 halogen from the exact location you plan to upgrade and note the alignment tab position. If the tab will sit at 12 o'clock (top) after installation, choose H7A - the wire will land at 6 o'clock (bottom). If the tab will sit at 6 o'clock (bottom), choose H7B - the wire will again land at 6 o'clock.
Because H7 housings vary by manufacturer and model year, the safest approach is always to confirm with the actual bulb in hand before ordering.
Images provided by Morimoto.
Which version do I usually need?
Use this as a starting point only. For H11 HID conversions, H11B is the most common choice. Start by looking at how the original halogen bulb sits in the headlight: facing downward usually points to H11B, while facing upward is the less common situation where H11A may be needed. The actual headlight should always be checked before ordering, especially on vehicles with projector headlights, factory HID/LED packages, or replacement housings.
| Housing / position | Common H11 HID choice | Common H7 HID choice | Notes |
|---|---|---|---|
| Most H11 HID conversions | H11B is most common | Not applicable | H11B is the normal starting point for most H11 HID kit orders because it places the return wire at the bottom of the bulb. |
| Original H11 halogen faces down when installed | H11B is most common | Not applicable | This is the usual H11 HID orientation. The goal is still return wire down after the HID bulb is locked in. |
| Original H11 halogen faces up when installed | H11A can be needed | Not applicable | This is the less common H11 HID situation. Use H11A only when the installed bulb orientation requires the opposite return-wire position. |
| Standard H11 halogen applications | H11B is usually correct | H7A or H7B depending on housing | Common H11 examples include Toyota Camry, RAV4, Tacoma; Honda Accord, Civic, CR-V; Ford F-150, Explorer, Escape; Chevrolet Silverado 1500, Malibu, Equinox; and Nissan Altima or Rogue. H7A is common in BMW 3 Series, 5 Series, and X5; Volkswagen Jetta, Golf, Passat, and Tiguan; Audi A4 and A6; and Mercedes-Benz C-Class and E-Class (where H7 is the OEM low beam). Confirm package and bulb location. |
| Hyundai / Kia H11B halogen applications | Usually H11B, sometimes H11A | H7B may be used in some H7 locations | Hyundai Sonata, Hyundai Santa Fe, Kia Optima, Kia Sorento, and similar applications are common sources of confusion. Some vehicles list or use an H11B halogen bulb but still need an H11A HID bulb so the return wire lands correctly. |
| Projector or reflector high beam | Usually not a typical H11 HID high-beam choice | H7A or H7B depending on housing | High beams vary heavily, and HID high beams are not ideal for frequent flash-to-pass use because HID systems need warm-up time. |
BRI Source note: H11A is a rare aftermarket HID orientation, not a normal halogen bulb type. OEM H11B halogen bulbs can also have a different connector design, so the stock halogen name and the HID A/B choice may not match. If your vehicle originally uses an H11B halogen bulb and you are not sure which HID orientation you need, contact us before ordering.
How to verify A or B on your vehicle
Remove the original halogen bulb from the exact location you plan to upgrade.
Look at the alignment tabs and whether the installed H11 halogen faces upward or downward.
Picture where the HID return wire would sit once the bulb is locked in place. The target is wire down.
Choose the A or B version that keeps the return wire away from the most important part of the beam.
- For H11 HID bulbs, H11B has the return wire at the bottom of the bulb and H11A uses the opposite orientation.
- If the H11 halogen faces downward in the headlight, H11B is usually the correct HID orientation; if it faces upward, H11A may be needed, but that is the less common H11 HID setup.
- If the return wire points straight through the hotspot or cutoff area, output can look darker or uneven.
- If the tabs put the return wire toward the side, choose the version that best matches the preferred direction for that housing.
- If your vehicle uses factory HID, factory LED, or an unusual projector setup, do not order from this guide alone.
- If you are unsure, send BRI Source a photo of the bulb opening and original bulb orientation before ordering.
Note: If you are installing an LED bulb rather than an HID kit, none of the above applies. LED bulbs are clockable and have no return wire. Orientation is adjusted after installation by rotating the bulb.
A few important details
- HID conversions may require relay harnesses, CANBUS modules, anti-flicker modules, or vehicle-specific wiring support.
- Hyundai and Kia applications are common exceptions, especially Sonata, Santa Fe, Optima, and Sorento models with H11B halogen listings.
- Some LED/HID upgrades may be intended for off-road, show, auxiliary, or permitted-use applications only. Check local laws before using upgraded forward lighting on public roads.
- HID bulbs are not a good replacement for every housing. Beam pattern, glare control, and product quality matter.
- Bulb size charts can be wrong when a vehicle has multiple headlight packages. Confirm the actual vehicle before ordering.
We can help confirm the right version
Send us your year, make, model, trim, bulb location, and a photo of the original bulb or headlight opening. We can help you decide whether H11A, H11B, H7A, H7B, or another setup makes the most sense.