FlywireFlywire helps provide ultra-lightweight support and comfort for your foot. It gets its strength from thin Nylon fibers strategically placed on the upper of the shoe to hold the foot in place, helping to reduce slippage during activity. This allows for a massive reduction in weight because material is used only where it s needed for structure.LunarlonA cushioning system made up of a soft yet resilient foam core, encased in a supportive foam carrier for a lightweight blend of ultra-plush cushioning, springy response and support.FlyknitAn innovative upper material, constructed entirely of tightly woven polyester yarn that varies in density: more open in targeted areas that need greater flexibility or ventilation and tighter in areas that demand support. Precise knit construction process integrates stretch and support for a more exact fit. CUSHIONING: Lunarlon OUTSOLE: Blown rubber forefoot lugs/ Flex grooves MIDSOLE: Lunarlon cushioning UPPER: Flyknit/ Fitsole sockliner/ Reflective elements/ Pull-tab on the heel