Tire Safety Information TIRE FUNDAMENTALS Federal law requires tire manufacturers to place standardized information on the sidewall of all tires. This information identifies and describes the fundamental characteristics of the tire and also provides a tire identification number for safety standard certification and in case of a recall. 188.8.131.52 Information on Passenger Vehicle Tires Please refer to the diagram below. 47 P The "P" indicates the tire is for passenger vehicles. Next number This three-digit number gives the width in millimeters of the tire from sidewall edge to sidewall edge. In general, the larger the number, the wider the tire. Next number This two-digit number, known as the aspect ratio, gives the tire's ratio of height to width. Numbers of 70 or lower indicate a short sidewall for improved steering response and better overall handling on dry pavement. R The "R" stands for radial. Radial ply construction of tires has been the industry standard for the past 20 years.
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