HOKA ONE ONE Challenger ATR 3 Running Shoes Synthetic 3D Puff Print Frame - Lightweight and offers a secure fit. Lightweight No-Sew Speedframe Construction - Eliminates chances of any chafing or irritation. EVA Midsole - Provides essential low profile cushioning. Meta-Rocker - Helps for accurate roll through the gate cycle. Durable Rubber - Helps to prevent the shoe wearing in key areas.