Gravel Grinder ProMake your mark on the gravel scene with the Gravel Grinder This tire combines a fast rolling diamond center with aggressive shoulder knobs that only hook up when the terrain gets soft, muddy, or a bit sketchy This handmade clincher combines a supple, 260TPI SuperPoly casing with natural rubber tread for long distance comfort, confident cornering, and quick handing. Includes PPS2, a combination of our sub tread Puncture Protection System and an