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  Walkie-talkie is a two-way mobile communication tool, in the case of not needing any network support, you can talk, no call charges incurred, suitable for relatively fixed and frequent call occasions.
  Walkie-talkie currently has three major categories: analog walkie-talkie, digital walkie-talkie, IP walkie-talkie.
  On the current procurement of walkie-talkie products the largest number of departments and units, it seems to illustrate the problem. Public security, armed police, firefighters, car clubs, donkeys, site construction, property, scheduling, security, etc. are the main user groups of walkie-talkie products.
  According to the different uses of different user groups, the walkie-talkie products used are not the same, mainly the volume, set up mode and communication distance difference.