See also:

Tread
The part of the tire that comes into contact with the road. ...

Tire labeling overview
The following markings are on the tire in addition to the tire name (sales designation) and the manufacturer's name: 1 Uniform tire Quality Grading Standard 2 DOT, Tire Identification Number ...

Setting the center air vents
1. Center air vent, left 2. Center air vent, right 3. Center vent thumbwheel, right 4. Center vent thumbwheel, left •► To open/close: turn thumbwheels 3 and 4 up or down. ...