Mushroom grow room humidifier. Integral adopting integrated type ultrasound machine, no mechanical drive, no noise, producing certain negative ion and low failure rate, easy maintenance. The output fog grain diameter being only between 1-10 micron. Stain less steel powder coated body, beautiful appearance, standard filling water mouth, switch and outlet water spill. Automatic water level controller. High atomiziation efficiency. Producing small and even fog. Water saving. High RH accuracy as ultrasonics provide instant on/off of mist, as soon as the air strays from the relative humidity setpoint, the ultrasonic humidifier instantly turns on.