Snapsafe A Hornady Company Hygrometer LCD display AAA Battery. This small hand-held instrument sits on the shelf inside your safe or cabinet and records the temperature and relative humidity in the environment. The digits of the hygrometer represent the percentage relative humidity of the environment. To record the current reading remove the digits from the scale and set your home/business/shop relative humidity. The Snap-Safe Hygrometer is a small hand-held weather instrument that you can mount almost anywhere. The digits of this weather instrument measure the dew point (ambient) and the dew point (external). To record the current reading simply lift the digits off the scale. Specifications for Snapsafe A Hornady Company Hygrometers: Manufacturer: Snapsafe A Hornady Company Color: Black Quantity: 1 Package Contents: Snapsafe A Hornady Company Hygrometer Snapsafe A Hornady Company 75909: Hygrometer LCD display AAA Battery