An easy-to-use and inexpensive sling psychrometer. Quickly determine dew point and relative humidity with the wet-bulb/dry-bulb technique. Includes two thermometers mounted on stiff vinyl backing, wet-bulb sleeve, sling handle, and mounting screw. A reproducible instruction sheet provides concept explanations, psychrometer chart, and sample calculations. Classroom set includes materials to make 15 psychrometers.