【About Wifi connection】 Please note the wifi video intercom system does not mean it's wireless and u don't need any cable.The monitor support WIFI network,but the indoor monitor and doorbell is Wired, which make sure the power,the video work stable and you can extend longer distance. 【Multiple Intercom】Up to 2 doorbells can be connected with 4 indoor monitors(The slave monitor is MZ-VDP-739EM). Dual-Way Communication between indoor monitor and outdoor camera; Call Transfer among monitors.You don't always go downstairs open the door after install the multiple intercom. 【Automatically Snapshot or Recording】When visitor press the doorbell or triggered motion detection, the camera will automatically snapshot or video recording and save in the Micro SD card(SD card need to purchase separately).You can check the recording via smartphone anytime. 【7 Inch LCD Monitor and Mini Doorbell】 7 inch TFT display monitor with slim design,touch-key operation,hand-free, Support Wifi/RJ45 port connect to internet(Only connect to 2.4GHZ router band). Outdoor doorbell with waterproof cover, built-in infrared sensor and 1200TVL camera, 100º wide view angle, Night vision,Rainproof,Dustproof,and Anti-vandal, It can connect all the electronic lock.