The Vaillant vSmart 0020197226 Combi Boiler smart thermostat is a white, wall-mounted programmable thermostat designed for central heating radiators. Made of plastic, this digital control thermostat offers 7-day programming with temperature sensor technology for efficient heating control. With its corded electric power source and digital display, this Vaillant smart thermostat is perfect for maintaining a comfortable and energy-efficient home environment. You can use this to control your heating where ever you are as long as you have WiFi or 4/5g phone signal. Used - works great - just upgraded my heating