Humidifies up to 1??000 sq. ft. through the use of signature vortex circulation</br>Adjustable humidistat for automatic humidity control and 3 speed settings (low?? medium?? high)</br>4 gallon capacity and up to 4 gallon output every 24 hours for long?? uninterrupted operation</br>Airlock water tanks are easy-to-fill?? spill