Cooper Weather-Master Winter Radial Tire - 215/55R18 95T Tire only Directional tread design improved snow acceleration and water evacuation. Patented circumferential snow-groove technology enhances snow-on-snow grip capabilities. High sipe density design increases biting edges for improved ice and wet traction capability. High-silica, low modulus tread compound adds superior ice, slush and wet grip even in extreme, cold temperatures.