Features: 1. A lightweight and compact communication device 2. Provide you clear and loud sound 3. Can be used to keep communication with partners or workmates 4. Built-in 2800mAh battery for long service time 5. Prevent users from receiving unauthorized signal and avoid the interference channel 6. Protect sound from the interface of signal 7. Suitable for many occasions, such as airports, manufacturing plants or concerts etc .
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