The EXT+ version is enhanced with an additional protective layer of Panaracer ProTite shield material from lug to lug for even more protection against tread and sidewall cuts on extra tough trails full of sharp rocks.the tire is otherwise based on the same concept as the Gravelking and Gravelking SK models, incorporating the same ZSG Natural Compound technology, which creates a softer compound that is overlaid on the outside with a harder compound for increased durability.aX-Alphacord technology uses the highest density, flattest fibers possible for flexibility, lightness and increased puncture resistance. The thick tread pattern is specially designed to perform at its best in mud and poor conditions. Tubeless ready.