These devices installed at the entrances of retailers’ shops help stop pilferages. They work with tags on products so that an attempt to take out a product without getting it billed sets off a beeping alarm. The use acousto-magnetic technology. The devices also do traffic intelligence – how many people enter the store, how much time they have spent on particular shelves e.g. food, cosmetics, electronics, etc. They also have artificial intelligence, not yet applied locally, that tells a retailer of how many people pick up an item and put it back without buying it. They also do source-tagging through Radio Frequency (RF) technology, which helps a retailer, for instance, to know how many units of a product are available without their having to go and physically count them.