Features: * Thermostatic radiator valve (TRV) is a self-regulating valve attached to radiators of the hot water heating system, to control the temperature of a room by changing the flow of hot water to the radiator. With the TRVTV02, you can conveniently adjust the room temperature between 5-30, and save more than 15% energy. *The radiator thermostat fits all standard radiator valves and is easy to install - without having to drain water or interfere with the heating system. *The additional boost function allows the radiator to heat up briefly by opening the valve for 5 minutes. *There is a pleasant room temperature immediately due to the radiated heat. *The product's holiday mode. If you plan to leave the house for a few days, the holiday mode starts automatically and maintains the set temperature. which helps to save energy and reduce unnecessary costs. Prompt: This product must be used with a smart hub Specifications: Temperature range: 5-30 Dimensions (W x H): 101 x 59 mm. Operating temperature: -10 - 40 . Working environment: Indoor Frequency: 2.4 GHz. Scope of delivery: 1 x thermostat. resp. 3 x thermostat. resp. 3 x thermostat. 1 x intelligent hub.