Uniform Tire Quality Grading
Uniform Tire Quality Grading, commonly abbreviated as UTQG, is a set of standards for passenger car tires that measures a tire's treadwear, temperature resistance and traction. The UTQG was created by the National Highway Traffic Safety Administration in 1978, a branch of the United States Department of Transportation (DOT).
Source: Wikipedia — Uniform Tire Quality Grading (CC BY-SA 4.0)