P Metric
With the P-Metric system, Section Width is measured in millimeters.
To convert millimeters into inches, divide by 25.4. The Aspect Ratio (Section Height divided by Section Width) helps provide more dimensional information about the tire size.
Example:

(1) P = Certain tire type used on light duty vehicles such as passenger cars
(2) Section Width in millimeters
(3) Aspect Ratio (= section height 7 section width).
(4) R = Radial Construction
(5) Rim diameter in inches
See also:
Changing a flat tire
WARNING
● Do not jack up the vehicle on an incline or a loose road surface. The jack
can come out of the jacking point or sink into the ground and this can result in
a serious accident.
...
Flat tires
If you have a flat tire while driving, never brake suddenly; keep driving straight
ahead while gradually reducing speed. Then slowly pull off the road to a safe place. ...
Trailer hitches
Never drill the frame or under-body
of your vehicle to install a commercial
trailer hitch. If you do, dangerous
exhaust gas, water or mud may
enter the passenger compartment
through the ...
