Felt sole GUIDESOLE Technology: The curved sole design and stiff forefoot of our GUIDESOLE technology reduce ankle flexion and provide a shock-absorbent landing zone to lessen fatigue of other leg muscles and increase runner efficiency. Engineered Mesh Upper: Multi-directional mesh material improves ventilation and stability. Rearfoot GEL technology cushioning system: Attenuates shock during impact phase and allows for a smooth transition to midstance. FLYTEFOAM Midsole Technology: Our FLYTEFOAM technology provides exceptional bounce back and responsiveness no matter the distance, utilizing organic super fibers to help reduce packing out that traditionally happens with softer, low density foams. Engineered Mesh Upper: Multi-directional mesh material improves ventilation and stability.