Tuya app WiFi Door and Window Sensor Alarm, Home Office Apartment Safety Door Magnetic Alarm, no Cost, no Need for hub, (Set of 2)

The door and window sensor is connected to your phone through WIFI. Once connected, whether you are at home or outside, it will immediately notify your phone when the door and window are opened or closed.
Door and window sensors are not only installed on doors or windows, but also on garage doors, wine cabinets, wardrobes, cabinets, safes, pet doors, etc.
Door and window sensors do not require a hub and do not charge any fees. Pair our application with Alexa or Google Home to understand the status of the door sensor without the need for a mobile phone. When it opens or closes, you can easily check your doors, windows, cabinets, drawers, or any place you want to notify.
The door and window sensors do not require any installation tools. After connecting to WIFI, open the back cover and install 2 AAA batteries. Fix them with double-sided tape where they need to be installed., You can find how to add sensors to the app on the homepage or in the user manual. This sensor is low-power and easy to install, with an ultra long battery life. Two AAA batteries can stand by for at least 1 year
Door and window sensors require two AAA batteries (to be purchased by the user). When the battery is low, it will automatically push a message through the app to remind you to replace the battery, never worry about running out of battery, so you can use it with peace of mind.