This item is provided by Crutchfield.com and includes free phone technical support for the life of the product. Details on how to take advantage of this service will be included with your package. Should you have any issues locating information on how to contact Crutchfield Technical Support, please contact this website's Customer Service department. The Nest Temperature Sensor lets you monitor the temperature in baby's room, and set your Nest Thermostat to keep it comfortable. Monitor "room temperature" in your smart home Your heating and cooling system tries to make your whole house one temperature. This 3-pack of Nest Temperature Sensors lets you monitor individual rooms - say, the baby's room, the kitchen, and the living room - so you can tell your Nest Thermostat to tailor its heating and cooling to whichever room you're in. Just place a Nest Temperature Sensor in any room and wirelessly connect it to your Nest Thermostat E or Nest Learning Thermostat (3rd Generation) . Then you'll be able to get granular with the scheduling. Set your thermostat to keep the baby's room warm overnight, or cool the kitchen down during the hectic morning hours. It gives you more data points, so Nest can do a better job keeping you and yours comfortable. You don't have to stop at three. You can add up to 6 sensors to each Nest Thermostat you own (with a grand total of 18 per household) and use them to refine your ability to monitor and control your Nest system. What's in the Box: 1. 3 Temperature sensors 2. 3 Self-tapping screws (length 1-1/8") 3. 3 QR codes (one attached to each sensor) 4. Set up card 5. Limited Warranty