http://www.newsweek.com/what-are-run-flat-tires-how-do-they-work-1701463 > The world of tires is an ever-expanding nexus of increasingly specialized compounds for any situation. There are tires for everyday roads, snow, rain, summer, racing, off-roading and tires that attempt to handle multiple terrains. > A smaller slice of the tire market is the run flat tire, which usually appears on luxury or heavy vehicles. Basically run flat tires have a contingency built in that allows a driver to continue on the road if it experiences a puncture, allowing them to get somewhere safely for a replacement.