Free app warnings: When the door/window is opened or closed, the window sensor sends an instant notification to your smartphone. Place it on a medication box to track if the elderly is taking their medication, or place it in your pet's cage to know if your kitten is discovered. Detects people who leave or enter home: with the built-in motion sensor, the contact sensor detects whether you leave the house or come, and allows you to trigger the various actions you set in the "scene" in the Tuya Smart app. When it detects you leave the house, the devices turn off automatically and when it detects you come home, the devices turn on automatically. Compatible with Alexa and Google Home: No hub required and no fees. By connecting to 2.4 GHz Wi-Fi, you can pair the Smartlife app with either Alexa or Google Home and enjoy the status of your door sensor without having to use your phone. Free your hands with voice control. Easy to install and low power warning: thanks to the small and wireless design, you can install window alarm sensors without tools and set up in seconds. The garage door alarm requires 2 x AAA batteries (not included). When the battery level is low, it will automatically send messages through the app to remind you to change the battery. HIGH QUALITY AND WORRY FREE SALE: Our home security alarm system is 100% tested before leaving the factory. If you have any questions about the door alarm sensor, you can contact our customer service at any time. We will solve it for you and satisfy you. Please rest assured to buy., Manufacturer: RISOON