... We have been working on video door phone and video intercom for 6 years, we are marketing:1, 4 wire CX ... :1, Audio/video communication, 7'' TFT LCD color display;2, Intercom, inspection and Remote unlock;3, Support extended phone set;4 ... ;NW: 0.64kg GW:0.73kgInstallation method: flush mounting. video intercom