Not many sneakers can boast of being designed to have a pre-determined lifespan. Usually the brands always stive to produce products that last, but with the Mayflys Nike had a specific goal to create a running shoe that could last to run 100 kilometers - no more no less. It goes without saying that it was never designed to break. It was however designed by the lightest available materials at that time, and boasted a the promise of "dying after 100 km.". Surely more a marketing stunt than anything, however the fact is that Nike Mayfly is one of the most comfortable summer shoes imaginable.