The new One 2.5 is built for speed, without sacrificing the comfort needed to maintain it through the finish line. A FootShapeâ⢠toe box lets your toes relax and move freely for incredible comfort, extra stability and a more powerful toe-off. Innerflexâ⢠technology adapts to the flexion of your foot with omnidirectional flex grooves in the midsole. Responsive A-Boundâ⢠cushioning protects the feet at impact and rebounds to add a spring to each step. The weight-balanced, Zero Dropâ⢠platform helps you maintain low-impact form, even when fatigue sets in at the end of a hard race or workout. Go fast, go hard and stay comfortable from step one to the finish line with the new One 2.5.A-Boundâ⢠and EVA midsoleA-Boundâ⢠TechnologyApprox. 0mm heel-to-toe offsetApprox. 23 mm stack heightApprox. weight: 5.2 oz/147 gCushioned footbedFootPodâ⢠OutsoleFootShapeâ⢠Toe BoxInnerFlexââ¢Lace entryPadded collar and tongueQuick-dry air mesh and synthetic upperZero Dropâ⢠PlatformStyle Number: A2523-2