The square-lugged open-tread pattern offers stability in loose or wet terrain, while the stiff outside knobs grip at lean angles like nobody business. Updated tire profiles provide a smoother transition from centerline to side knobs and improve predictability while cornering. Improved knob shapes prevent knob flex by reinforcing the specific areas that counteract cornering and braking forces. Updated siping eliminates knob squirm while also increasing traction on wet or rocky terrain. Tough – A double layer of light casing, TCS Tough tires are composed of two full layers of casing, bead-to-bead, leaving no area unprotected on our burliest tires. FR – Fast Rolling, with WTB`s Dual DNA rubber compound that optimizes efficiency, traction and durability, A firm, long-wearing centerline tread with softer side knobs. TCS – WTB`s Tubeless Compatible System, sealant based tubeless system with improved bead shape. TT – WTB`s new triple compound, TriTec featuring a hard base level, medium center knobs and softer shoulder knobs for improved traction and performance. EBIKE25 – has achieved a passing rating for use with E-Bikes up to 25kph.