Firestone Destination M/T Mud Terrain Radial Tire - 31R15 109Q CO-CS (Computer Optimized Component System) combines tread design, materials, and construction to create optimal tire performance Dura-loc technology resists on- and off-highway hazards L.L. Carbon (Long Link) resists cracking and tearing, improving tread wear and tire life O-bead enhances comfort through a single, continuous cable in bead construction