The road running shoe for city streets gets a performance upgrade with soft Helion™ superfoam and breathable fabrics. One-piece knitted upper The shoe's snug bootie construction is updated with a single-piece knitted upper for maximum airflow. The perforated toe box further boosts breathability. Dual-density midsole For a cushioned yet energetic ride, the midsole's top layer is made with soft Helion™ superfoam, while denser foam on the bottom provides a more propulsive push-off. Optimized support We updated the design and fit of the shoe's iconic cage construction for better midfoot lockdown. Plus, it's now finished with a new knit material for a more modern look.