A run-flat tire is a pneumatic vehicle tire that is designed to resist the effects of deflation when punctured, and to allow the vehicle to continue to be driven at reduced speeds under 90 km/h and for limited distances ; usually 16 km to 80 km, depending on the type of tire.
Run-flat tires are designed with special technology that allows the tire to continue to function even when it has low or no air pressure. This is usually achieved by reinforced sidewalls or internal support layers that support the vehicle's load even when air pressure is lost. With run-flat tires, the driver does not have to immediately replace the tire or stop the vehicle in a dangerous place if a puncture occurs. This improves safety and comfort, especially when driving on busy roads or in adverse weather conditions
