Reebok ZigNano Rhythm Running Shoes ZigNano Sole - One-of-a-kind zig-zag-shaped sole, absorbs the impact of heel strike and propels you forward, while reducing wear and tear in key leg muscles PU sockliner - For added cushioning and support. Flex Grooves - At the forefoot for enhanced flexibility and a better range of motion. Non-Marking Rubber Outsole - For added durability. Synthetic and Mesh upper - Ensures ultimate comfort, snug fit and durability.