Article number: 4009816020284 View all of TFA > View more: Hygrometers > TFA - Hygrometer humidity and temperature Save on gas or energy by monitoring the humidity in your home or office. When the humidity in your home or office is high, heating the room costs more energy than when it is low. You can measure humidity with hygrometers. Then you know whether you need to ventilate the room better or whether you need to increase the humidity. These factors influence the humidity level in a room: plants and pets the number of people (due to breathing and perspiration) the degree of ventilation the use of humidifiers activities that use water, such as cooking, showering and mopping. Product specifications Hygrometer Innen - Humidity and Temperature Item description Hygrometer Innen - Humidity and Temperature Item number 4009816020284 Type Analog Type Measuring = Knowing Measuring range outside temperature: 0°C to 40°C Measuring range humidity: 100% With metal ring No battery required