The Hygro-Thermometer I got yesterday and tried the same in all the rooms of my apartment and office. It reacts at room change quickly to changes in temperature and humidity. Surprised at first made me the very compact design, because with 5.3 cm x 3.9 cm x 1.9 cm (LWH), it is smaller than I thought. But that is not a disadvantage, because it consumes really very little space and is still good and clearly readable. The Min / Max function can be exploited to see, between which values z. B. move the room temperature and the relative humidity in the bedroom during the night. Especially during the winter season it's good to know whether the humidity and temperature in the different rooms where you are staying, in the "green zone" are, or whether it is better set up dehumidifiers in order to counteract a mold, or water evaporators should attach to the humidity in the health good area - keeping (45 55% relative humidity.). For this, I can only recommend the small device. The only shortcoming: The operating instructions are kept in very small print.