The electromagnetic wave system of the supermarket anti-theft door has the smallest label, and the price of the label is also cheap. It can be repeatedly demagnetized, but it is vulnerable to the influence of magnetic or metal substances and generate false alarms. The width of the protected exit is generally about 0.9 meters. The system will not affect magnetic objects (such as audio tapes, video tapes, magnetic cards).

The working principle of the supermarket anti-theft system is: attach an electronic anti-theft tag to the goods that are small in size, large in value and easy to be stolen, and there is an anti-theft door at the exit of the mall. When the thief steals the goods with the tag through the inspection door, he will immediately call the police (like the boarding check at the entrance of the airport), while the normal shopping will make the tag invalid and will not call the police when passing the cashier. For supermarkets and clothing stores that often lose goods, Franchise stores and other business places can greatly reduce losses