Design: Atomknit, an updated version of Flyknit, has a lightweight, contoured fit and enhanced breathability, It works with a new knit structure and midfoot containment cables to give you an ultralightweight upper Bill Bowerman, inspired the Blueprint collection design details, like the speckled Swoosh logo and sketches of feet on the insole Durability & Traction: The full-length carbon fiber Flyplate is tuned to match the base of the support system the shape and stiffness give a propulsive feel to keep you on your toes and minimize deceleration Elevated the big-toe side platform to help the spikes feel more stable on the straightaways and especially around the turns The new plate material is lighter than the previous version, two spikes seen on the original were removed in favor of a four-spike design Additional Details: Designed for 800m - 5000m events