What is a ‘tyre fitment’?

The tyre fitment for a vehicle refers to the tyre size(s) approved for the vehicle.
The fitment consists of the following:

• Width: Width is the first 3 numbers, and represents the width of the tyre in millimetres.
• Profile: Profile is the next 2 digits, often separated by a slash. The profile of a tyre is the height of the sidewall, as a percentage of the overall width.
• Rim: Rim size follows as the next 2 digits, usually following "R" and is the inner diameter of the tyre measured in inches.
• Speed rating: Speed rating is the final letter, and indicates the maximum speed the tyre is approved for.