1、Main Function: This GSM analog alarm can fully monitor the state of 4‑20mA, 0‑5V transmitter, DC voltage, AC. 2、Unique Deisgn: The user can dial the device number through the authorized number, and the device will automatically reject the call and immediately send the current status SMS message to the caller. The user can also query the current status through the SMS command. 3、Support Multi Numbers: Support 10 authorized user numbers, alarm can be received alarm SMS, the last 5 authorized numbers can also receive alarm phone reminder. 4、Cloud Platform Connecting: It also supports Modbus RTU and Modbus TCP to connect to the cloud platform, and can monitor the current status through the network in real time. 5、Easy to Install: This GSM analog alarm is made of premium metal material, which is durable, stable and can be used for a long time. Item Type: GSM Analog Monitoring Alarm Material: Metal Operating Voltage The standard power supply is 12VDC, which ranges from 0 to 36VDC Power Consumption: 20mA12V; Maximum power consumption: 150mA12VGSM/3G/4G: GSM Frequency: 850/900/1800/1900MHz (default) The SIM Card Port: Support 3V SIM card External Antenna: SMA antenna interface,50 ohms Supported Protocol: for Modbus RTU Over TCP. for Modbus TCP Analog Input 0~5V/4~20mA Built in Battery: 3.7V/900mAh lithium battery *1 (built-in), sustainable working for 8 hours Operating Temperature: -10℃~60℃ Operating Humidity: Relative humidity 95% (without condensation) Size: Approx. 70 x 88 x 30mm / 2.8 x 3.5 x 1.2in(L x W x H) Application: 1 x Alarm 1 x Antenna 1 x Power Adapter 1 x Instruction