With gate crowding becoming more common, American Airlines is implementing new technology to prevent unauthorized early boarding for travelers in later boarding groups.

American Airlines has rolled out boarding technology that alerts gate agents with an audible sound if a passenger tries to scan a ticket ahead of their assigned group.

American Airlines has introduced a new solution to stop boarding line cutters, and it comes with a distinct sound. As reported by CNBC, the airline’s latest system emits a two-tone beep when a passenger attempts to board before their group is called.