Wi-Fi opening sensor. No hub required. The sensor works independently 2 years from the battery. Ready to work out of the box: the battery is already installed, so the sensor does not need to be disassembled. Connects to the application in one click. Mounted in a few minutes. Android / iOS app - Smart Life. Work as part of a smart home: Alexa Echo, Google Home, IFTT, Tuya. Work without 220V and wires.