Anion function : Air negative ions can restore from atmospheric pollutants, nitrogen oxides, cigarettes and other active oxygen, oxygen free radical, reduce excessive reactive oxygen species to the harm of human body; The air is cleared after the neutralization of the positive electric air. Timing functions : Intelligent anti-dry, 4 hours automatic power, safe and reliable; Timing function is more reassuring. Colorful night light : The diffuser has 7 colored LEDs for a beautiful, soothing atmosphere or the use as night light. Low noise : Ultrasonic technology make sure that your work or sleep will not be interfered by it. The humidifier is so Whisper-quiet with elegant mist. Eco- friendly : Environmental friendly ABS and PP, nontoxic, odor-free, corrosion resistant and durable. Compare with similar items. Read Less