BUY WITH CONFIDENCE This humidifier was designed and manufactured in the USA by AprilAire – the inventor of the whole home evaporative humidifier. and the leader in indoor air quality solutions FULL COVERAGE up to 5.300 square feet in tightly built homes with a capacity of 18 gallons per day MANUAL HUMIDIFIER with a single sensor built into the standard control monitors indoor relative humidity for use in manually setting the percent humidity in your home BUILT-IN FAN pulls heated air directly from the furnace through the humidifier HUMIDITY FOR HEALTH AprilAire Humidifiers can help you maintain optimal humidity in your home of 40% – 60% so you'll feel more comfortable while also preserving items in your home susceptible to damage from changing humidity or dry conditions -