The 9.0-gallon Recirculating Humidifier offers contemporary styling and efficient humidification up to 3,200 square feet, making it ideal for multiple rooms and large living areas. 9.0-Gallon Output per Day (4.5-Gallon Water Capacity); Easy-to-Fill, Removable Water Reservoir with Dual Handles; Adjustable Humidistat for Personalized Comfort; Patented, Cascading Waterfall Shows it's Working; Castors for Mobility on any Surface; Three Comfort Control Speeds; ETL/cETL Listed.. Comes with a filter