Save Energy Durable Replaceable Brand New. Thermostatic radiator valve (TRV) is a self-regulating valve fitted to hot water heating system radiator. To control the temperature of a room by changing the flow of hot water to the radiator. You can conveniently adjust the room temperature between 5-30? And save more than 15% of energy. The radiator thermostat fits to all common radiator valves and is easy to mount-without having to drain any water or intervene in the heating system. The additional boost function enables the radiator to be heated up quickly for a brief period of time by opening the valve for 5 minutes. There will be a pleasant room temperature right away because of the radiated heat. The holiday mode of the product. If you plan to leave home for a few days, the holiday mode will automatically start and maintain the set temperature. Which helps to save energy and reduce unnecessary expenses. Prompt: This product needs to be used with an intelligent hub. Dimensions(W x H). Please kindly note that. Also, the each additional item means. The the same color and size. Transit time may be a little delayed because of the. If you have any questions.