Test your fastest speeds in the Nike Women's Zoom Structure 19 Flash Running Shoe. A downright sprinter, this shoe features Nike's Zoom Air unit at the forefoot to propel your next step forward by delivering highly responsive, low profile cushioning. Dynamic Support uses crash rails to help the triple density midsole slow the rate of pronation for a better heel to toe transition. The waffle tread rubber sole has deep flex grooves for better mobility. Nike also designed this shoe with a three layer, water repellent, abrasion resistant mesh upper, Flywire cables for a secure fit, and an internal heel counter for snug fit.