The currently most widely used label in the electronic article surveillance is an RF-label. These labels are used in almost all sectors, so far from supermarkets, department stores to professional markets.

The construction of an RF label is quite simple. The electronic part of the label is aligned on the bottom and is usually applied directly with a permanent adhesive on the product. A coil which also serves as an antenna is connected to a small capacitor. Together they form a resonant circuit with an external high frequency field of about 8.2 MHz. When an activated label approaches the vicinity of the detectors (Gates), which are usually placed at the exit of a store, the radio-electronic oscillator circuit triggers an alarm. The deactivation of electronic article surveillance is usually done after payment at the cashpoint, either by mechanical control of the electronic part or by electrical manipulation.

RF-tags are for single use only, so-called "Hard-Tags" in contrast are reusable. In a lot of products (for example shoes) RF-components are implanted during the manufacturing process and will remain there till the end of the products life cycle.

The covering material on the top of the label is usually made of paper but can also be PE or PP material. The label can be imprinted with the particular information by a suitable printer. It also can be pre-imprinted by us, for example with a colored corporate symbol or it could be delivered with a so-called "blindcode". Also conventional is the so-called "nature-version". This is intended for discouraging among the electronic effect as well.

Pros:

• Low cost
• The possibility to combine electronic retail security and pricing

Cons:

• An RF tag is always tied to a minimum size
• Тhe electronic oscillator circuit can be relatively easily manipulated by metallic and magnetic objects or electronic devices.

Source: http://webcache.googleusercontent.com/search?q=cache:CSVTCtPUm90J:www.zackl.org/index.php/rf-labeltech-as.html%3Flang%3D+&cd=1&hl=bg&ct=clnk&gl=bg