HomeGardenWorld Mini Ultrasonic Aroma Diffuser Air Purifier Humidifier Night Light Color Change Negative ions are known to help reduce illnesses and protect against germs in the air, resulting in decreased irritations. Smoothly changing colored light filtered through bubbling water . Lasts 4 hours on the highest setting - 8+ hours on low setting. Independent 3 million Anion setting . Variable mist adjustment. Multiple LED light settings - Automatic color change, Single color settings and LED off. 360-degree mist nozzle rotation .