Breathable Mesh Upper - A highly breathable upper also built with synthetic upper for greater durability. * Nike Free Technology - This shoe delivers the feel of training barefoot with a natural fit and enhanced flexibility. * Dynamic Fit System - It tailors the shoe perfectly to your foot and provide a great fit. * Strategically Placed Carbon Rubber - Under high-wear areas for durability. * Reflective Details - For keeping you safe in low light conditions.