Panaracer: Gravel, dirt or rough pavement. The most durble version of the “GravelKing SK” series. The strongest version of GravelKing SK now has even better puncture resistance, with the use of ProTite Shield Plus for withstanding tough conditions. Developed with ZSG compound to enhance durability and wear resistance. Lightweight, ultra-thin 'Ax-Alpha Cord' has been used to make it even lighter in weight.