More cushioned than the Nike Free RN Motion Flyknit, the Nike Free RN Flyknit Women's Running features a newly designed midsole pattern that expands, flexes and contracts with your foot with every step. Its sock-like upper provides the incredible fit of Flyknit for total comfort throughout your run. Move Naturally The next-generation Nike Free midsole expands in multiple directions thanks to an entirely new tri-star pattern, adding a new dimension of flexibility that lets your feet move more dynamically with every stride. Plus, the heel is rounded to mimic the shape of your foot and roll naturally with the ground. Soft Cushioning Softer than previous iterations, the new midsole foam delivers exceptionally comfortable cushioning and lightweight durability for miles. Incredible Fit The single-seam Flyknit upper provides an incredible sock-like fit with targeted areas of high breathability, stretch and support. Flywire cables woven into the upper can be tightened through the laces for dynamic support that moves with you. More Details Non-stretch heel material for added structure Rounded heel for natural range of motion Lightweight solid rubber segments under the toe and heel for enhanced traction and durability Weight: 174 grams approx. (women's size 5.5) Offset: 8mm 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.