<https://www.aihub.my/product/aihub-door-window-sensor/#product>
<http://schema.org/description>
"Monitor and detects opening &amp;amp; closing of doors, windows, cabinets in real time.\r\n\r\nAiHub Door/Window Sensor uses the distance between the magnets inside the sensor and the magnet to determine the present status of doors or windows. It is also energy-efficient, the sensor has a battery life of 1 year (30 triggers per day)"
<https://www.aihub.my/product/aihub-door-window-sensor/>