We got to hand it to our friends at Madelaine! Sure their gel crystals in small jars were a great product, but to put them inside a humidifier....why didn't I think of that.....what an awesome idea and a fabulous product! The gel crystals are enclosed in clear polycarbonate humidifier case. The humidifier has the crystals inside which will hold up to 450 times its weight in solution. The crystals soak up the solution and it creates that wonderful gel which stays saturated with PG solution. Watch the crystals, when they shrink to about half their swelled size, re-charge them with PG Solution. With this humidifier you will never let your cigars go dry again! A magnet attachment system holds the unit firmly under the lid of your humidor.