Since we have mold in our home, I had bought this hygrometer to measure the humidity can. To protect against a bad buy, I also bought the larger model (TFA "Comfort Control" digital thermo-hygrometer) to compare the two can. Both showed almost the same values and therefore I assumed that these values were correct. (Humidity is always between 65% -80%). Now we were then nevertheless times an appraiser come with professional equipment and lo and behold: The moisture values were 20-30% too high given. The values from the evaluators indicated normal humidity and temperature less than the TFA devices. Unfortunately, I can the two models no longer send back ... very annoying !!! NO KAUFEMPFELUNG!