This 25mm Ultrasonic Humidifier Moisture Film Humidification Piezoelectric Transmitter module works on the principle of cavitation produced by sound waves. As sound waves contain compression and rarefaction. Due to extremely rapid movement, water droplets can no longer sustain their liquid state and get converted into vapor immediately. This vibration is produced by a piezoelectric filament.Application : Medical liquid atomizing. Humidifier.Beauty care for facial massager. Equipment. Features : High stability. Low noise operation Small fog particles. Low noise operation. Long operation life. Package