Rubber sole An updated design gives you a more responsive, lighter and softer foam than previous versions. Laser-cut flex grooves offer more flexibility, with rubber at the forefoot and heel for durability. The upper uses a breathable knit material throughout for a soft, stretchy feel. It gives your foot room to stretch as you run. Flywire technology is looped through the laces on the side for midfoot containment. The same cushioned heel you know and love from previous iterations of the Free provides comfortable support. A pull tab at the heel provides easy on and off. The sock-like fit and lightweight feel of this Nike Free Rn 5.0 2021 Mens Shoes was made to transition from running to training to your everyday routine. Made from at least 20% recycled content by weight, it combines the flexibility you love with a contained design that will help keep you close to the ground for that barefoot feeling. A new foam is lighter, softer and more responsive than previous versions so you can keep moving in comfort whether you're on the tarmac or the track.