![CPVAN Indoor Motion Sensor Alarm with Siren, Remote Control Wireless Infrared DIY PIR Motion Detector Burglar Alarm System, 125dB Adjustable, Battery Operated, for Home/Shed/Garage/Van.: Amazon.co.uk: DIY & Tools CPVAN Indoor Motion Sensor Alarm with Siren, Remote Control Wireless Infrared DIY PIR Motion Detector Burglar Alarm System, 125dB Adjustable, Battery Operated, for Home/Shed/Garage/Van.: Amazon.co.uk: DIY & Tools](https://m.media-amazon.com/images/I/61shmVoD9-L._AC_SY450_.jpg)
CPVAN Indoor Motion Sensor Alarm with Siren, Remote Control Wireless Infrared DIY PIR Motion Detector Burglar Alarm System, 125dB Adjustable, Battery Operated, for Home/Shed/Garage/Van.: Amazon.co.uk: DIY & Tools
![Intelligent Wireless WiFi Motion Detector Intruder Sound Light Alarm Door Window Contact Magnetic Sensor by Phone Remote Control for Home Security Auto System - China Alarm and Detector Intelligent Wireless WiFi Motion Detector Intruder Sound Light Alarm Door Window Contact Magnetic Sensor by Phone Remote Control for Home Security Auto System - China Alarm and Detector](https://image.made-in-china.com/155f0j00ejKVhPgJGScZ/Intelligent-Wireless-WiFi-Motion-Detector-Intruder-Sound-Light-Alarm-Door-Window-Contact-Magnetic-Sensor-by-Phone-Remote-Control-for-Home-Security-Auto-System.jpg)
Intelligent Wireless WiFi Motion Detector Intruder Sound Light Alarm Door Window Contact Magnetic Sensor by Phone Remote Control for Home Security Auto System - China Alarm and Detector
![4” diameter motion sensor (?) on the ceiling of my new apartment. Makes a tiny click when you move under it. Can't remove it, and no idea what it could be for. : 4” diameter motion sensor (?) on the ceiling of my new apartment. Makes a tiny click when you move under it. Can't remove it, and no idea what it could be for. :](https://i.redd.it/3arxv0egb3g01.jpg)