1. GSM monitor
2. Voice activated function  
3. SMS to control voice activated on or off
4. GSM door magnetic alarm
5. door magnetic sensor alarm  
6. door magnetic sensor
7. Battery volume checking function by sending SMS
8. Anti-thefting, door watcher
9. 2 in one of GSM monitor + door magnetic sensor

Features  

1. the world's infinite distance voice transmission ( using the GSM signal transmission, no distance limit can be inter-provincial cross-border) ; 
2. ultra-clear sound
3. Small size like a match box, portable
4. 900/1800 or 850/1900 frequency   
5. With lithium battery inside too ( 70-150 hours standby for voice control,or 120-240 hours for withoutvoice control ) . Send GDM3 to check battery volumme .
6. Voice activated function:
   Send GDM1 to start voice activated control
   Send GDM2 to stope voice activated control
7. Door magnetic sensor control ( means if your door is opened ,the alarm will send a message to inoform you that your door is opened ); 
   Send GDM4 to start voice activated control
   Send GDM5 to stope voice activated control