LW15 2-in-1 Room Humidifier and Air Purifier with Auto Shut-Off Feature. The LW15 Venta Airwasher Humidifier/Air Purifier humidifies dry room air while simultaneously purifying it by helping to remove dust, pollen, pet dander, and other allergens. Venta Airwashers do not use filters; water is the filter. This makes the Airwasher easy to maintain and clean. Additionally, Venta Airwashers do not produce the "white dust" common with other humidifiers due to the fact that it uses cold water evaporation technology. Designed for rooms up to 200 sq ft, this Airwasher has a 1.4 gallon capacity. This Venta Airwasher has 2 Speeds and also features Auto Shut-off. This 2-in-1 Humidifier/Air Purifier is perfect for any type of room.Engineered for tough jobs, Venta's portable humidifier and air purifier features a patented disk stack system, which draws air into the unit and pushes it through sheets of water, washes dirt and dust out of the air, leaving cleaner, humidified air in the surrounding indoor space. Venta Airwashers were designed with advanced technology and German engineering, making them the best room humidifers and purifiers on the market. Features: Dual-function: humidifier and air purifier in one Compact, efficient, and powerful for indoor air spaces up to 200 sq. feet. Low maintenance - just add water Auto shut-off feature and low water warnings Light and durable - weighs only 7 lbs Eliminates unpleasant odors like stale tobacco smoke Accommodates all water densities, soft or hard Energy efficient, requires little power ( Simple to use with on/off light and speed controls 2X year worry-free cleaning No ions, no white dust; will not over-humidify Recommendations for Optimal Use: Clean twice a year for maximum performance with the Venta Cleaner. Easily remove the electric components and ventilator for a full clean. Use year-round for a healthier, cleaner lifestyle at home or work. Prevent calcium and lime build-up with the Venta Water Treatment Additive.