The Nike Flex outsole expands and contracts to allow your foot to move naturally from heel-strike to toe-off. Breathable Comfort
Breathable fabric in the forefoot and internal sleeve helps keep your feet cool and comfortable. Supportive Fit
Flywire technologystrong, lightweight cables that provide supportbring a secure, locked-in fit through your midfoot. More Benefits Dynamic Fit technology provides a secure, adaptive fit Soft, responsive Lunarlon cushioning helps absorb impact Loosely woven fabric in the forefoot for natural stretch Weight: 249 grams approx. (men's size 9) Offset: 4mm
Nike Free Origins After learning that Stanford athletes had been training barefoot on the university's golf course, three of Nike's most innovative and creative employees set out to develop a shoe that felt natural and weightless, similar to bare feet. The team spent eight years studying the biomechanics of runners' feet in motion. The results yielded a profound understanding of the foot's natural landing angle, pressure and toe position, allowing Nike designers to build an unconventional and flexible running shoe from the inside out.