From: Thermometers and Thermostats : Thermometers & Weatherstations
With a Wireless Thermometer all you need to do is mount an outdoor sensor that will then send information to your indoor receiver. This allows you to find the perfect space to mount your thermometer without having to worry about cords or wires. This lets you place it in the most temperature critical location for accurate temperature sensing. Using a Wireless Indoor Outdoor thermometer lets you easily monitor conditions inside and outside your house.
This compact Wireless Digital Thermometer with Hygrometer has a clear readout and is simple to set up. The main unit records the temperature and humidity indoors and the sensor supplied measures temperature wherever it is placed, whether in your garden,outbuildings or greenhouse.