Midsole / outsole: Using FEA technology, we simulated and analyzed different outsole designs in order to find the optimal geometry for improved durability. Speedboard: For the softest and smoothest running sensation, we engineered the Cloudsurfer 2 without a Speedboard – instead, relying on our structural cushioning system: CloudTec Phase. Upper: Breathable mesh upper made from 88% recycled polyester. Embroidered overlays – also made with recycled yarn – provide support and structure around the foot.