The 7” TFT Screen Monitor & FHD Camera Video doorbell System B104 is an innovative intercom system that has been designed to meet the communication needs of modern residential buildings. With its advanced security features, ease of use, versatility, affordability, and quality assurance, this intercom system is an ideal communication solution for anyone looking for a reliable and cost-effective communication system. Place your order today and enjoy the benefits of a top-quality intercom system. This 7” TFT Screen Monitor & FHD Camera Video doorbell System B104 can be connected by only 4 wires. 4 wires mean video core, audio core, 12V DC, and GND. It is for villa houses and supports extra  CCTV cameras and alarm sensors. This KIT has a wide-view angle outdoor unit and a 7" indoor screen. The outdoor station and indoor monitor are 4-wire hard-wired. Built-in power supply and external power adaptor for optional. No matter what kind of house, you can find a suitable solution in Royal Gates!