There are 3 types of electronic systems, using different principals and having specific advantages and disadvantages. Therefore they are suitable for specific applications. All systems operate in combination with tags or labels attached to the product to be protected which respond with a small signal when passing the EAS antennas. Radio-Frequent or RF systems RF systems are used in all kinds of retail outlets and are the most popular. The system consists of  two antennas or sometimes one single antenna covering about one meter (40”) from the center of each antenna.

RF systems are versatile and are relatively cheap in purchase and maintenance.

Various labels are available, such as low-cost sticker tags, soft tags and hard tags, in various specifications.

Electro – Magnetic or EM Systems the label used is a small thin strip of 1.5” till 3” long consisting of  a specific alloy of magnetic and ferrous material, which can be hidden quite easily.

Because of the low frequency the strip can be directly attached to metal surfaces. EM systems are used e.g. in hardware stores, bookstores and record stores. The detection range is about 50 cm (20”) from the center of each antenna. Because the EM strip can be deactivated and (re-)activated, EM systems are also very suitable for library management.

Combined technology systems For example Electro-Acoustic Systems manufactured solely by Sensormatic from the USA used in various retail applications.

The advantage of Electro-Acoustic system is that it uses dual technology which reduces the chance of false alarms. The phenomenon of false generally alarms occurs in older (analogue) RF or EM systems. The labels applied are small. A disadvantage, besides costs, is that the system is not supported by any other supplier.