An absolutely functioning mechanical hygrometers which comes close to expensive electronics parts! The device comes with me in a room used (brick interior wall!), Which is equipped with a sauna room. If one considers the instruction manual, you can start from a very long life. Since no button cells are needed as in the electronic measurement application, acoustic control signals remain ("beeping" for automatic change of display or decrepit battery!). The "thing" was purchased on the recommendation of Stiftung Warentest (Note 1 in the test of mechanical hygrometers!) By me and has convinced me completely !!!
