Commodity security system single and dual channel options

Commodity anti-theft systems are divided into single-channel and dual-channel, so how do we choose in practical applications? An example is given below.
Bookstore and library anti-theft system: choose electromagnetic wave anti-theft system, because the magnetic strip is generally longer, so if the door exit is within 1 meter 4, it is recommended to choose a single channel, and the general manufacturer can install it at a distance of 75-90CM. If the exit is more than 1 meter 4 and less than 2 meters, it is recommended to choose dual channels. If it is more than 2 meters, choose four or more to achieve;
The clothing store anti-theft system can choose either radio frequency system or electromagnetic system. The reason is that the anti-theft system is implemented through hard tags. The difference is that the inner body of hard tags is different. Supermarkets generally recommend choosing radio frequency systems.
Pharmacy anti-theft system: It is recommended to choose electromagnetic wave system. Because the medicine is relatively small, it is recommended to choose a magnetic strip between 3-8 cm. Generally, a 3-6 cm magnetic strip can be charged and degaussed, and an 8 cm magnetic strip can be selected. The reason is that The shorter the magnetic strip, the worse the alarm effect of the device, and the rechargeable and degaussing strip is stronger than the permanent magnetic strip.