NIKE Women's Air Relentless 3, Magnet Grey/University Blue/Hyper Grape/Metallic Silver, 10 B - Medium Synthetic-And-Mesh Imported Synthetic sole A running shoe built for the neutral to underpronator who requires enhanced cushioning Durable water repellent (DWR) treatment helps keep the elements out Air-Sole unit in the heel provides the right balance of cushioning for a smoother ride