Cooper Tires Discover A/TW Radial Tire - 255/70R18 113T Tire only Micro-gauge corrugated siping optimizes all-terrain performance with an emphasis on winter traction. SnowgrooveTM2.0 provides better mechanical locking of snow into the grooves which generate higher snow-on-snow traction forces. Twin tie-bars provide stability for confident handling and reduces irregular wear for longer tread life and a quieter ride. Asymmetric dual-draft groove angles reduce the tire's tendency to retain stones and rocks, extending the life of the tire.