How does anti theft GPS tracker works?

anti theft GPS tracker: The user sends a car search instruction SMS to the SIM card in the GPS terminal, and the GPS terminal returns the location.

4G Mini Vehicle GPS Tracker Anti Theft for Vehicles - China GPS Tracker, Car Device Tracking

Vehicle Tracking and Anti-theft System using GPS-GSM

IP65 Waterproof 7500mAh Big Battery GPS Tracking Device for Car Truck Anti- theft - AliExpress

Instant Motion Detector with GPS Tracking, 1-Month Free Subscription, Instant Anti-Theft Alerts, Works 24/7, Lock to Your Luggage, Vehicles, Bikes, Bags, etc

abs plastic GPS Trackers Wireless Bluetooth 4.0 Anti-Lost Anti-Theft Alarm Device at Rs 100 in Delhi

Car GPS Tracker Real Time Tracking Device GPRS Locator Truck Vehicle Anti Theft

How GPS Vehicle tracker works

Car Gps Tracking Device Locator Real Time Anti-theft Alerts Location Terminal Support App/sms/platform Tracking Over-speed/geo-fence/vibration Alarm H

Bike Tracker and Bike Alarm - BikeFlare

TKSTAR 4G GPS Tracker for Vehicles OBDII Car GPS Tracker Real Time Anti Theft Tracking Device for Vehicles, Cars, Truck, Bus, Off-Roader - Yahoo Shopping