Challenge Grifo TE S are the standard by which other tires are judged, ridden to countless victories over the years. Challenge Grifo’s race proven Team Edition “S” softer tread pattern works in all conditions, if you have one tire, this is the one. The supple Sealed Corespun Cotton 330TPI casing gives you precise control at low pressures and is water-resistant; no need for external sealant. CHALLENGE’s famous SEAMLESS LATEX Tube reduces rolling resistance and is protected by PPS (Puncture Protection Belt) between the tread and the casing. Removable Valve Core.