Nexkin upper: Reduces the shoe's weight while increasing durability against abrasions from rocks and roots. An asymmetrical lacing system: Reduces pressure across the top of the foot. Lace garage: Helps keep the laces from coming untied. 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. FLYTEFOAM cushioning: Provides impact absorption. Colour: red