12 Head Ultrasonic Mist Maker Fogger 3.5A36V 350W Mist Maker Fogger Air Humidifier w/Transformer Accessories for Industrial Scenic Agriculture Greenhouse Hydroponics Garden/Lawn/Pond. Ultrasonic mist makers work by creating ultrasonic vibrations that atomize just about any fluid that you put it in. The lighterweight the fluid, the more mist produced. It creates a small boil on the waters surface that releases the "fog". It is very quiet compared to most humidifiers. To operate, just set the transducer in the float, place it in your water, and plug it in. Voila! The unit will automatically shut itself down after the water level becomes too low. These can be used in countless applications. Many use these to raise the humidity level in their greenhouse's or even in their homes. It can also be used in the hydroponic propagation of plants, from cuttings to maturity, however; I would not recommend the single head mist maker for growing plants beyond a cutting. For full term growing I would use at least a three head mist maker. Other uses include pesticide application and so on.