The Cigar Caddy 4 oz. Crystal Gel Humidification Jar is a must have for your humidor. This crystal gel humidifier is designed to effectively maintain a nice 70% humidity inside your humidor keeping your cigars nice and fresh. The polymer crystals are super absorbent and can absorb up to 100 times their weight in fluid. It can last up to 90 days before a refill and regulates humidity for up to 150 cigars. As the crystals lose moisture, they begin to shrink making it easy for you to know when to add more distilled water.