1It can be operated from anywhere without distance restrictions. 2GSM temperature monitoring alarm can reject calls from authorized numbers without making a call. 3Multiple applications (temperature, power state, solar panel, DC voltage). 4Up to 10 authorized phone numbers, 5 can be used to answer calls or text messages, and 5 can be used for calls and text messages to generate alarms. 5A DS18B20 temperature sensor input with a temperature range of -55- + 125C and an accuracy of 0.5C.