Xikar Crystal 100 Humidity RegulatorXIKAR's crystal humidifiers are the best in the industry. Maintaining correct levels in your humidor is the most important thing. Nothing will do that better than a XIKAR crystal humidifier. The crystals swell to 30 times their size so the humidifier is 90% solution you won't have to worry about refilling the humidifier for months at a time. Using XIKAR Propylene Glycol Solution ensures that your cigars are maintained at a perfect level of 70%