Flywire technology wraps the midfoot and arch for ultralight, ultra-strong support and glove-like fit. Ultra-lightweight, springy Lunarlon cushioning for soft yet responsive shock absorption. Dynamic Support that adapts to your stride for stability. Single-layer, engineered mesh upper for ventilation and support. Reflective elements for enhanced visibility in low-light conditions. Environmentally-preferred rubber Waffle outsole for multisurface traction and durability. Weight: 8.1 ounces (women's size 8) Mesh inner sleeve wraps the foot for a plush, comfortable feel. Fitsole sockliner molds to the shape of the foot for a glove-like fit and improved underfoot support. Natural Motion engineering flex grooves for enhanced flexibility and a smooth, efficient stride. Nike+ ready.