Mijia Door & Window Sensor
Model MCCGQ01LM manufactured by Xiaomi
Mijia Door & Window Sensor
low battery warning
Zigbee ID: "lumi.sensor_magnet"
Confirmed working with

Pairing Instructions
Press and hold the button on the device until the blue light starts blinking, release it and the pairing should begin.

If you're having connection or pairing issues read Xiaomi & Aqara Devices - Pairing & Keeping them connected.