WiFi Door Alarm System, 8-Piece DIY Wireless Alarm Kit with Door Sensors

WIFI Network: WIFI connection, Only works on 2.4GHz WiFi network, does NOT support 5GHz WiFi networks.
SMART ALARM SYSTEM for Home: tolviviov Alarm Security System is an affordable solution for your apartment security. You have full control over the door alarms for home security through your smartphone and get instant notifications of alarms alert in your house or apartment.
CUSTOMIZATION: You can add extra door and window sensors, motion detectors, wireless doorbell, and water detectors to different rooms in your home security systems;It supports expansion of up to 20 sensors and 5 remote controls/keypads, which can be added to the WiFi alarm station.