The Resideo C7089R1013 RedLINK external Temperature and Humidity Sensor is designed for the accurate measurement of external temperature in HVAC systems. This thermistor range of -40°F to 140°F and humidity range of 0% to 100%. This is vertically mounted on the wall for easy installation and reliable operations. This sensor works with Resideo’s RedLINK-enabled thermostats and zoning systems and optimizes HVAC performance by providing current outdoor conditions. Advantages include better climate control, energy, and system performance since inside settings change according to exact outside conditions.