(A) Passenger (P-Metric) Tire : The United States
version of a metric tire sizing system. The letter P
as the first character in the tire size means a
passenger vehicle tire engineered to standards set
by the U.S. Tire and Rim Association.

(B) Tire Width : The three-digit number indicates
the tire section width in millimeters from sidewall to

(C) Aspect Ratio : A two-digit number that
indicates the tire height-to-width measurements.
For example, if the tire size aspect ratio is 60, as
shown in item C of the illustration, it would mean
that the tire's sidewall is 60 percent as high as it is

(D) Construction Code :  A letter code is used to
indicate the type of ply construction in the tire. The
letter R means radial ply construction; the letter D
means diagonal or bias ply construction; and the
letter B means belted-bias ply construction.

(E) Rim Diameter : Diameter of the wheel in inches.

(F) Service Description : These characters
represent the load index and speed rating of the
tire. The load index represents the load carry
capacity a tire is certified to carry. The speed rating
is the maximum speed a tire is certified to carry a
Tire Size Numbers Description
Tire Size Example
P 235 / 60 / R16   97S
|       |            |        |    |            |
A     B          C       D   E          F

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