The humidor hygrometer is a device for measuring the relative humidity of air. Classic Analog hygrometers use a metal spring and sponge system that varies in accuracy +/-10%. Analog hygrometers intended purpose is to offer a classic enhancement to aesthetics. Superior digital hygrometers close the gap in accuracy to about +/-2%. Digital hygrometers are a recommended solution to customers who buy humidors that value accuracy and as an addition to the analog hygrometers that are synonomous with our collection of humidors. Stogieshumidors provides a 30 Day Satisfaction guarantee on all of our cigar humidor hygrometers.