What does run-flat technology allow in a car?

A run-flat tire is a pneumatic vehicle tire that is designed to resist the effects of deflation when punctured, and to enable the vehicle to continue to be driven at reduced speeds. These tires contain an extra lining within the tire that self-seals in the event of a small hole due to a nail or screw. In this way, the loss of air is prevented from the outset such that the tire is either permanently self-repairing or at least loses air very slowly.