Shenzhen Ninth District Technology Co., Ltd. is mainly engaged in the design, development, manufacture, sale and technical service of high-tech communication and electronic products. At present, the company's main products are mobile phone signal screening device, GPS shielding device, mobile phone signal amplifier and other products. All the products of the company have their own intellectual property rights. The mobile signal amplifier is widely used in the basement, the hotel, the elevator and some other blind areas. The cell phone signal shield is used in the conference room, the auditorium, the court, the library, the examination room, the school, the theater, the hospital, and the gas station, the gas station, the oil fields and the oil depots. The government, military, financial, financial, securities, prison, public security or command center, such as all places to prohibit the use of mobile phones and many fields, GPS shields for personal vehicles, anti positioning and tracking products are stable and reliable, and have been widely recognized by the users.