Challenge Gravel Grinder Tire 700x42C Folding Clincher Vulcanized Nylon 120TPI BlackMake 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 clincher with 120TPI nylon casing provides both performance and durability. Includes PPS, a Puncture Protection System placed between the tread and casing to increase resistance to punctures. TECH SPECS Primary Color Black Bead Folding Tire