... features:1.Use SIM900B GSM module---industrial module .Two-way voice to communication,to talk with people who ... LED defense zone, four wired defense zone3. The system supports the GSM cell phones, no need the ... Can set HOME arm/AWAY arm5. When alarming, system plays the recorded voice at first, call six ... panic from long distance. 9. Can control the system by using a telephone or cell phone anytime, ...