Google Nest Temperature Sensor 3 Count Pack - Nest Thermostat Sensor - Nest Sensor That Works with Nest Learning Thermostat and Nest Thermostat E - Smart HomeWorks with compatible Nest thermostats [1]; the sensor tells the thermostat what the temperature is in the room where its placed and the thermostat uses that reading to control when the system turns on or off to keep that room the temperature you like. Google Nest Thermostat Compatibility: Communicates temperature to compatible Google Nest thermostats up to 50 feet away. Low Energy Bluetooth Connection: Up to 6 Google Nest Temperature Sensors