Gravel - Challenge Gravel Grinder Race Tire, Folding - 700 x 33, Handmade - Babymaker ModelsIntended for all around or dirt gravel roads, this tire comes equipped with a file tread center and a knobbier shoulder tread. File tread center pattern offers low rolling resistance on smoother terrain and increased grip when the road gets rough Shoulder tread is more aggressive for corner confidence and additional control The Gravel Grinder is ideal for hardpack, gravel, sand, loose, and rocky terrains Compatible with BM II ISO Diameter: 622 Road