Falken Ziex S/TZ-05 All-Season Radial Tire - 305/50R20 120H All-season performance and comfort for luxury SUV's and light trucks Five-rib symmetric tread design provides increased high-speed stability and the freedom of tire rotation, enhancing tread life. Wide shoulder blocks increase tread stiffness allowing for maximum wet and dry handling and stability. Solid center rib offers excellent handling response especially in high-speed conditions. Wide and narrow shoulder lug grooves designed to optimize noise reduction.