FREE APP ALERTS FOR PEACE OF MIND: No hub required; The window door contact sensor is controlled by Tuya Smart App or Smart Life App. An alert notification will automatic send to you once the sensor triggered; A must have security system accessories VOICE CONTROL: The Smart door sensor is compatible with Amazon Alexa and Google Assistant, Simply give a voice command to check if your door is open or close, such as "Alexa , is the front door open?" SMART HOME AUTOMATION: You can set a condition in the smart scene, Automatically turn on your smart wall switches or lights when door opened; or the air conditioner in your room is turned off once your window is open. More smart devices can be sync as long as they compatible with Smart Life app. SMART SECURITY SENSOR: All alarm record history can be check in app; All the statuses of doors and windows will be displayed simultaneously in the app; Share the device to your families, they can check the status and get notified at the same time APP remote control is connected to the app via WIFI without a hub.After the connection, the user can monitor the status of the doors and windows anytime, anywhere. Colour:White Material:ABS Note the features: 1. [APP remote control] Remotely set the arm and disarm at any time through the mobile phone APP 2. [One-click arming] You can set one-click arming, which is more convenient to use. 3. [Voice control] Used with Amazon Alexa and Google Home, you can check whether the doors and windows are open or closed 4. [Sharing function] Share with family members and control together 5. [Offline function] When the device is offline, the APP will remind the device to be offline after 30 minutes 6. [Low battery reminder function] The product uses 2 AAA batteries (not included). When the battery is low, the phone will remind you to re