Calculate the relative humidity of air using this device.  Includes two identical thermometers.  The wet bulb thermometer has a wicking cloth material over the bulb and is connected to an included water reservoir.  Thermometers are graduated in Celsius -10° to +50° (1°C) and Fahrenheit 14° to +122° (2°F). Includes humidity table in C.  Dimensions: 11.5" x 3" x 1.75".