Vornado HU1-0013-11 Standard 4-Gallon Vortex Humidifier Large-capacity storage; soothes dry throats, prevents dry skin, alleviates congestion Automatically maintains selected humidity level Evaporates 4 gallons water in 24 hours at high speed Humidity control and three-speed fan; bedroom-quiet on low 20 by 13 by 11-1/2 inches; 5-year warranty