This pair has some wear with about 17 miles of use, but they still have plenty of life left. The Endorphin Pro 4 running shoe is a miraculous feat of engineering: snappy and responsive yet smooth and efficient. Something we achieved by fusing PWRRUN PB and PWRRUN HG together in the midsole – an industry first. A full carbon plate adds longitudinal stiffness and maximum metabolic efficiency. And the silky-smooth heel liner and integrated tongue system makes this marathon shoe feel like slipping on an old friend come race day. Carbon plate is engineered for longitudinal stiffness and maximum metabolic efficiency. Snappy SPEEDROLL technology - effortless speed and propusive forward motion. Race-ready fit - Silky smooth heel liner and integrated tongue for a connected comfort.