... status.10. Auto-detect and report, GSM Signal WEAK alarm, SMS Switch is available. >>>>>Functions & Features of the King Pigeon ... 12VDC>>GSM Frequency : Quad-Band 850/900/1800/1900MHz>>Communication protocol: GSM PHASE 2/2+ (include data service)>>Wireless sensor ... a professional GSM Alarms, GSM Alarm Systems, GSM SMS Alarm, GSM SMS Controller,GSM Automation system,GPRS Data Logger,Temperature Logger ...