The Nike ReactX Pegasus Trail 5 uses a mesh woven upper, with a tighter weave in high wear areas like the toes, giving you a highly breathable feel, with all the durability you need to hit the trail in confidence. Add in flywire technology and you get a locked in fit at the midfoot that helps you take on uneven terrain. ReactX has a been developed over a 5-year period and provides a 43% reduction in the carbon footprint of a pair of midsoles, and increases energy return by 13%, giving you improved performance for the planet, and for your runs. The outsole uses a generative traction pattern for excellent grip and runs up over the front of the foot to improve durability.