Speed Rating: The maximum speed at which a tire is certified to carry a load. Speed ratings range from A (lowest) to Z (highest), with one exception: the H rating falls between U and V. Q is the lowest rating commonly used for cars

Treadwear: The wear rate of a tire when tested under controlled conditions. The codes set forth in the UTQGS are two- or three- digit numbers representing a percentage of a standard value when a tire is tested in accordance with specified procedures. The higher the number, the better the wear.