2012 Toyota Prius Owners Manual - Page 1380

6-1. Specifications Tire related term Meaning The linear distance between the exteriors of the sidewalls of an inflated tire, excluding elevations due to labeling, decoration, or protective bands That portion of a tire between the tread and bead The parting of the rubber compound from the cord material in the sidewall A tire that attains a traction index equal to or greater than 110, compared to the ASTM E1136 Standard Reference Test Tire, when using the snow traction test as described in ASTM F-1805-00, Standard Test Method for Single Wheel Driving Traction in a Straight Line on Snow-and Ice-Covered Surfaces, and which is marked with an Alpine Symbol ( least one sidewall ) on at Section width Sidewall Sidewall separation Snow tire Test rim The rim on which a tire is fitted for testing, and may be any rim listed as appropriate for use with that tire That portion of a tire that comes into contact with the road A tread section running circumferentially around a tire 6 Tread Tread rib Vehicle specifications 523 PRIUS v_U (OM47784U)