Review on Goabroa Hygrometer Thermometer Temperature Fahrenheit by Eric Smithlin

Works well. The accuracy of available gauges is generally plus or minus 5%. If you need to know how much to add or subtract from the reading, you can make a paste of salt and water in a bottle cap, seal the cap and meter in a plastic bag for 8 hours, and read the difference between the reading and 75 %. , then remember to correct the reading by that amount. Repeat every 6 months. Others are outraged by the 5% error, but I don't know how to do better for a reasonable price.