Easy to use, simply unwrap, add PG Solution, and place the humidifier in your humidor. Slow, steady release of constant humidity of 70% . Clear polycarbonate cases house crystal gel saturating 450 times their weight with XIKAR PG solution! Magnet attachment system holds the unit firmly under the lid of your humidor. 6 1/2in. across, 2 1/2 in. tall, 1/2 in. thick. Maintains up to 250 cigars in a volume of 1250 cubic inches at 70%.