Controls the Lightwave RF radiator valve Works as part of the Lightwave RF home automation system Allows each rooms radiator to be turned off when the window is open Simply sticks to your window frame Requires Lightwave RF radiator valve The Lightwave RF Connect Window Contact Switch is designed to work alongside the Lightwave RF Radiator Valve. If it is triggered by the opening of the window it is attached to it will automatically command the valve to turn off the radiator. If the window is closed again it will command the valve to turn the radiator back on. This simple & inexpensive but very effective device therefore can provide significant energy savings if positioned in a room such as a bathroom or childs bedroom.brbrbrbr