A cigar hygrometer
can work in various different ways, but the two most common types use a
synthetic hair, or two separate metal plates that use water to produce
electricity, to control when the humidor turns on and off. The humidor
is a component within most cigar cases that maintain the level of
humidity within the enclosed structure at the optimal levels that allow
the cigar to retain its original air dried flavor. One common problem
associated with cigars is that they dry out very easily, which changes
their flavor and smoothness. The humidor ensures that the cigar is
fresh, and the cigar hygrometer acts as an on and off switch for the
mechanisms that work the specific humidor.