Product introduction 4G GPS tracker for prisoners (GPS watch), using GPS/ Beidou positioning combined with GSM/GPRS network, with real-time positioning and data transmission and watchband anti-disassembly functions.the product has the advantages of convenient use, high supervision efficiency, low maintenance cost, safety and health to human body, no electromagnetic radiation pollution, safer use and so on.Each device has an independent identification IMEI number. When the data is uploaded to the background, it can complete the automatic identification of personnel, track tracking, and free interference automatic screening of legal identity, etc.Can be applied to execution outside prison staff attendance record, trajectory tracking, automatic access management, message notification, particularly in the security problem increasingly prominent today, all kinds of safety management and the real-time tracking of personnel in the industry needs more and more intense, wrist strap electronic tamper with its superior performance, reliability and cost-effective provides successful solutions for our customers. 1. Beidou/GPS/WIFI/LBS multiple precision positioning modes. 2. SMS receiving. 3. Two-way conversation. 4. Mechanical anti-dismantling alarm. 5. IP68 deep waterproof and dustproof rating. 6. Low energy consumption and long standby time. 7. Historical track query. 8. SOS emergency dialing alarm. 9. Electronic fence (forbidden) alarm. 10. Alarm in key areas (no entry). 11. Low battery, watchband disconnection, wristband falling off alarm. 12. Record of exercise steps 13. Body temperature/heart rate/blood pressure/blood oxygen monitowristband. 14. Date and weather display (to be added). 15. Make up the blind spot. 16. Camera function. 17. Touch display.