Nike Womens Free Tr Focus Flyknit Training Shoe (8 B(M) US, Mica Blue/Electro Green-ocean Fog-white) Mesh Upper : Breathable engineered mesh upper with lightweight synthetic material in key areas. Dynamic flywire provide support and stability in key training zone. Midsole & Outsole : Strategically placed rubber pods in heel and forefoot provide durability and traction.