This 4G mobile phone signal jammer ( https://www.jammermfg.com/cell-phone-jammers.html ) is a device used to block or interfere with mobile phone signal transmission. It transmits radio frequency signals to cover specific signal frequency bands in the target area, so that mobile phones cannot receive or send signals normally. This device is often used to protect privacy, maintain a quiet environment, or prevent mobile phones from being used in specific occasions (such as meetings, exams, etc.).

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