The scanner software recognizes metallic and non-metallic items hiding under clothing. The machine then processes an image using yellow boxes to point out any areas that may need additional screening.

When you pass through an Advanced Imaging Technology (AIT) body scanner in 2026, the "yellow box" or "yellow highlight" on the screen indicates an anomaly or "threat" area that the software's AI has detected. The scanner creates a generic "avatar" (often called the gingerbread man) rather than an actual image of your body. If the machine detects something with a density different from human skin—such as a forgotten tissue, a wallet, a heavy fold in your clothing, or a metallic object—it places a yellow box over that specific area on the monitor. This tells the TSA officer exactly where they need to perform a targeted pat-down. It is a common 2026 occurrence caused by even harmless things like thick hair, damp clothing from sweat, or bulky jewelry. To avoid the "yellow box," ensure your pockets are completely empty and you have removed all bulky accessories before stepping into the machine.