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Or they may equip their cars with self-sealing or run-flat tires, which Wardle said are “good if it is just a puncture from a nail but useless if you hit a pothole and split the rim and sidewall.”

Technical details of the Secret Service-operated limos are a closely kept national secret, but they are often described as having special run-flat tires in case of emergency.

According to Michelin, they weigh less than a traditional run-flat tire and wheel combination and that a driver won't notice any difference in performance.

Unlike run-flat tires, the technology aims to avoid the flat in the first place.

Instead, they have inflator kits or “run-flat tires,” which are designed to travel about 100 miles more until the driver can make a repair and write an angry letter or email in whatever jurisdiction the pothole was encountered.