Cooper DISCOVERER H/T All-Season Radial Tire - 235/75-15 105S 60,000 Mile Warranty Solid center rib improves steering response while reducing noise for a quiet ride. Four wide, notched circumferential grooves offer resistance to hydroplaning, while improving snow and soft-surface traction. High density zigzag sipes enhance wet traction and winter performance on snow and ice while maintaining tread element rigidity. Semi-closed shoulder design (exclusive notched shoulder rib) to provide long, even wear and increased cornering performance while also reducing noise.