Supermarket anti-theft door scanners, known as Electronic Article Surveillance (EAS), are a sophisticated defense against shoplifting. Invented in 1966, these systems use antennas at exits and tags on merchandise to detect unpaid items.

• The system relies on two main components: antennas (pedestals) and tags/labels attached to merchandise.
• There are two primary types of EAS systems: AM (Acousto-Magnetic) and RF (Radio Frequency), each requiring specific, matched tags.
• Cashiers deactivate EAS labels by passing them over a deactivator pad, often integrated with barcode scanners, or by removing hard plastic tags with a detacher.
• Some advanced tags feature self-alarming capabilities or hidden ink capsules to further deter theft.