Tyres Onyx 255/50 R20

The easiest and most reliable way is to check the size of the tyres you have used before. The picture shows how this information is provided.

Alternative variants of the tyre sizes can be found in the service and repair manual for your car. Furthermore, this information is specified on the pillar, on the front door end at the driver's side, on the fuel tank cap and on the glove box lid. But the best way is to check the size on the old tyres.