What is a Known Traveler Number and how does it relate to a Redress Number for expedited airport security screening?

A Known Traveler Number (KTN) is a unique identification code assigned to travelers who have been pre-screened and approved for expedited airport security screening through programs like TSA PreCheck. A Redress Number, on the other hand, is a unique identification code given to travelers who have faced difficulties during security screenings in the past. Having a KTN allows travelers to enjoy faster and more convenient security checks, while a Redress Number helps address any previous issues or misunderstandings that may have occurred during the screening process.