Federal Formoza FD2 All-Season Radial Tire - 235/55R18 100V Variable sub-grooves in the shoulder blocks reduce road noise 3-in-1 innovative groove design reduces vibration and pulsation frequency Wider Solid Central Rib increases straight line stability and on-center feel Wide circumferential grooves and tread pattern promotes rapid water evacuation and prevents hydro-planning for confident and safe driving on wet/damp surfaces