Xiaomi Aqara Quick Start Manual page 4

Door and Window Sensor
Aqara Door and Window Sensor detects the open and
close state of doors or windows through the distance
between the sensor unit and the magnet. It consumes
low energy. No tools required, and simply peel and
stick.
* A hub is required.
* Aqara Hub is required to enable Aqara Door and Window Sensor
to work with HomeKit technology. See www.aqara.com for more
details.
* This product is for indoor use only.
Sensor Unit Magnet
Quick Start Guide
Reset Button
Long Press for 3s: Reset
Single Press: Effective Range Test
Indicator Light