Adizero Prime X Strung Is Our First Ever Adizero Running Shoe With A Strung Upper. Strung Is A Textile Innovation That Transforms Athlete Data Into A Dynamic Material Tuned To The Athlete'S Needs. It Makes It Possible To Map And Program Different Fiber Properties Thread By Thread. With A Flexible And A Lightweight Seamless Cocoon Feeling Around The Foot, Strung Helps Optimize Your Comfort, And Supports You In Breaking Your Personal Best On Long Distance Runs. The Strung Upper Is Fused To A Prime X Outsole Packed With Carbon Energyrods And Three-Layers Of Lightstrike Pro For A Responsive Run.