Engineered for marathon performance, these sneakers feature three innovative technologies to enhance speed. Dual Air Zoom units combine with a full-length carbon fiber plate to provide energy return, while the Zoom X foam midsole ensures comfort throughout the race. two air zoom units in the forefoot zoomx foam midsole full-length carbon fiber flyplate atomknit upper wider carbon fiber plate for increased stability improved multidirectional containment and breathability fully connected zoomx foam midsole notched laces integrated knit tongue with lofted padding fits small, recommend ordering a half size up