signal jammer

In recent years, with the rapid development of mobile phones, it is not uncommon for students to use mobile phones to affect their lives and studies. Many teachers who patrol dormitories at night say that some students often use their mobile phones to go online in the bed, some even in the middle of the night. It is still at one or two o'clock, so in order to prevent students from playing with their mobile phones in the middle of the night, so that they can have a better rest, many schools have to choose to install cell phone jammer in their dormitories.
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