A: You'll have to re-fill this unit (add distilled water) about every 3 weeks. You'll feel the weight difference when it becomes dry. You should be able to use the unit continuously for 1-2 years, possibly more.
A: To get started, you simply have to soak the unit in distilled water. First, pick up some distilled water at the grocery store or drugstore for around a dollar a gallon. Place the humidifier in a bowl and add water until it is well covered. Allow it to sit for about 15-20 minutes. Remove humidifier and allow excess water to drain. Place in your humidor. After 3-4 weeks, the beads will become small (you'll feel the unit become significantly lighter). This is the time to add more water. Gently pour more distilled water into one of the holes in top, and allow to sit for 5-10 minutes. You can keep recharging the humidifier for at least 1-2 years, sometimes more.