Product Quality Hygro-Thermometer Made Of High-Quality Stainless SteelWith The Quality Hygro-Thermometer, Monitoring The Room Temperature Is Particularly Reliable And Comfortable. Comfort Zones Indicate When Ventilation Or An Increase In Humidity Should Take Place. So You Can Ensure A Comfortable Living Environment And Prevent Health Problems.Why Our Hygro-Thermometer: Mechanical Operation (Bi-Metal) Without Batteries Or Liquids High Precision And Insensitive To Interference High Quality Workmanship - Housing Entirely Made Of Stainless Steel And Glass (Without Any Plastic) Very Decorative And Of Great Nobility For Hanging Or Positioning (With Removable Bracket) Ready For Immediate Use And Calibration Screws For Adjustment If Necessary Fashion Instructions As An Attachment To The Invoice By E-Mail And As An Addition To The Device Support For Questions Concerning Application And CalibrationNote: Our Hygro- Thermometer Is Designed For Home Use And Gives Very Reliable Readings Within The Normal Measuring Range Of 25-80%Rh. Our Device Is Not Suitable For Applications In Extreme Measuring Ranges, Such As In The Sauna, Steam Bath, Etc. As With All Analog And Digital Hygrometers, A Certain Tolerance Must Always Be Taken Into Account In The Accuracy Of The Measurements. With Our Instrument, It Is Only +/- 5% Relative Humidity (Rh) Or +/- 1 (Temperature)