Take care of the air in your child's room so they can breathe easier. bbluv's Umi is an ultrasonic energy efficient humidifier and air purifier that has advanced technology and AST sensors. It is also ultra quiet and doesn't require filters to be changed out. Its air purifying function by ionization emits anions that capture the pollution particles in the air and neutralizes it very quickly. It maintains the level of desired humidity level in the room up to 28 hours and also includes an aroma diffuser. The Umi provides healthier air quality and a comfortable environment for the whole family.