This is a system comprising two or more antennas, visible or not, that detect the presence of an active label in a product, mainly a product that hasn’t been paid for.

The systems are classified as Radio Frequency, Acoustic-magnetic and Electromagnetic systems: radio frequency systems work with adhesive labels, paper labels and rigid labels.

The acoustic-magnetic systems, commonly used in perfumeries and pharmacies, work with a plastic adhesive label that is harder to hide and more expensive than radio frequency technology. They are implemented in all places where products susceptible to theft are sold to the public, at entry and exit points, in shops, warehouses or public libraries.