Feature: 1. 2‑wire system, only needs two wires, the power, audio, video and control signals are all transmitted through the 2‑wire non‑polar central power supply. 2. Use plug‑in connectors and DIP switches for quick installation. The integrated multi‑function and simple operation make the system more attractive. 3. Flexible cable connection, support in and out, branch and mixed mode. Support intercom communication between indoor units. Aluminum alloy outdoor unit, rainproof, anti‑oxidation and durable. 4. Using the integrated power supply, it supports up to 2 outdoor cameras and 6 indoor monitors (including only 1 camera and 3 monitors). 5. The camera has a built‑in white light LED night vision device that supports night vision effects. The monitor adopts 7in color TFT LCD, no radiation, low power consumption and high definition. The volume, brightness and contrast are adjustable. 6. Two locks can be unlocked at the same time. Support hands‑free intercom, mute indoor intercom function, group call/intercom function. Specification: Item Type: Video Door Phone Material: Aluminum Alloy + ABS Plastic Outdoor Camera: Aluminum alloy external device with white LED night vision goggles Camera: 1/3in CMOS 1000TV line Viewing Angle: 92° Minimum Illumination: 0.5Lux Video Output: 1Vp-p /75Ω Connection Method: BUS 2-wire Installation Method: Wall-mounted Working Temperature: -30℃ to 50℃ Size: Approx. 240 x 169 x 24mm/9.4 x 6.7 x 0.9in Monitor: Screen: 7-inch LCD Effective Pixels: 1024 x 600 Connection Method: BUS 2-wire Size: Approx. 151 x 80 x 38mm/5.9 x 3.1 x 1.5in How to Use: 1. Connect the indoor unit, outdoor unit and power supply with cables, and the power cord is connected to electricity 2. Adjust the color and brightness of the display, and use the intercom function of the doorbell 3. Connect the electronic lock at home to unlock the doorbell . Package List: 1 x Outdoor Camera3 x Indoor Monitor1 x DC24V 2.5A Power Supply1 x 4 Core Terminal Wire2 x 2 Core Connection Terminal Wire3 x 2 Hole Terminal1 x 3 Hole Terminal1 x 4 Hole Terminal3 x Bracket1 x Screws Pack1 x User Manual