OE Tire Markings Explained: ★, MO, N0, AO, T0 and More
What the carmaker codes on a tire sidewall mean, which brand each belongs to, and when it is worth buying the marked version.
Some tires carry a short code next to the size, such as ★, MO or T0. It means the tire was developed with a carmaker and approved as original equipment (OE) for its vehicles. The marked version can differ from the regular one in compound, construction or inner foam, even though the size and name are the same.
The common markings
| Marking | Carmaker | Notes |
|---|---|---|
| ★ (star) | BMW and MINI | Run-flat versions are often also marked RSC. |
| MO, MO1, MO-S | Mercedes-Benz | MO1 is used on Mercedes-AMG models; MO-S has noise-reducing foam. |
| MOE | Mercedes-Benz | Extended mobility: the Mercedes run-flat version. |
| N0, N1, N2… / NF0, ND0 | Porsche | The number is the generation; a higher number is a newer version. |
| AO, AO1, AOE | Audi | AOE is Audi’s run-flat marking. |
| RO1, RO2 | Audi | Mainly Audi RS and high-performance models. |
| T0, T1, T2 | Tesla | Often with noise-reducing foam inside. |
| J, JLR | Jaguar, Land Rover | |
| VOL | Volvo | |
| B, B1 | Bentley | |
| MGT | Maserati | |
| AR | Alfa Romeo |
Every product page on our site shows the OE marking, when there is one, with the carmaker it belongs to.
Do you need the marked version?
A marked tire is never required by law, and any tire of the right size, load index and speed rating will fit. But the marked version is tuned for the car it was approved on, so it is usually the best choice when:
- You drive a Porsche, or a performance BMW, Mercedes-AMG or Audi RS. These cars are set up around specific tires, and the makers recommend N-, ★-, MO1- or RO-marked tires.
- Your car has staggered sizes (wider at the back). Keep the same model and marking front and rear.
- You drive a Tesla or another EV. T0-type tires often add inner foam that cuts road noise, which you hear more without an engine.
- Your car came with run-flats (★ with RSC, MOE, AOE) and has no spare.
For everyday cars, or for winter tires, an unmarked tire of the right size and load is fine.
Rules of thumb
- Never mix different models, or marked and unmarked versions, on the same axle.
- Ideally fit all four with the same model; at the very least, keep pairs matched per axle.
- If you replace only two tires on an all-wheel-drive car, check the maker’s limit on tread-depth differences between axles.
Find marked tires
Search your size and look for the marking in the product name or specifications, or start from your vehicle under tires by vehicle. For electric cars, see EV tires.
Frequently asked questions
What does the star (★) on a tire mean?
It means the tire was approved as original equipment by BMW (also used on MINI). Run-flat versions are often marked RSC as well.
What does T0 mean on a tire?
T0 (and T1, T2) is Tesla’s original-equipment marking. These tires often have noise-reducing foam inside.
Do I have to buy OE-marked tires?
No, it is not required. Any tire with the right size, load index and speed rating fits. Marked tires are recommended mostly for performance cars, staggered setups and EVs, where they are tuned for the car.
Can I mix marked and unmarked tires?
Not on the same axle. Keep the same model and marking on both sides, and ideally on all four wheels.