PUMA Women's Faas 250 NM Running Shoe 100% Synthetic and mesh Rubber sole Features integrated BioRide Technology for a more natural and responsive ride Taxi AirMesh upper and PU overlays for comfort and support Open-hole mesh lining below the PU layer lends support as well as breathability Removable molded-KMS sockliner sculpts to your foot for the best possible fit Built-in flex grooves increase responsiveness while the groove in the heel reinforces stability on impact.