These humidity tubes are filled with a special gel polymer that, when added to distilled water, will expand to about 100 times their size. The tube features a fill line and add line so you know when you need to add some water to the humidifier to make the beads expand.
When you get this humidifier, it will have a plastic cap on it. Simply peel off the plastic and you’ll notice there is a perforated top. You’ll want to take the cap that already on there off – you can discard that – and you’re going to put the perforated cap on in it’s place. This is what’s going to allow the humidity to escape inside of your humidor.
Then you’ll need to fill the tube up with water – pop off the top, put just a little bit of water in and then put the top back on. You can probably go about 1-2 months before you’ll have to refill the tube with distilled water. Each tube will humidify approximately 25-50 cigars.Cigar Humidifier Demonstration: DryMistat Crystal HumidiTube by David Sabot