The Nest Temperature Sensor (2nd gen) makes it easy to manage hot and cold spots throughout your home. Just put it in a preferred room and get the right temp right where you want it. It's battery powered, so you can set it, then forget it's even there. [1] And it works with the Nest Learning Thermostat (4th gen), Nest Learning Thermostat (3rd gen), and Nest Thermostat E. [1, 4].