The cell phone signal shield is mainly aimed at all kinds of places such as examination room, school, gas station, church, court, library, conference center (room), theater, hospital, government, finance, prison, public security, military heavy ground and so on. It is understood that the mobile phone signal shielding device in the market can restrict the mobile phone signals outside 500M meters from the launch pad. The shielding radius is adjustable, covering a range of more than 30, and the mobile phone signal shield can only shield cell phone signals, but not other electronic devices. Save power, the power is 12W--480W.