Roow Air Purifier is intended to deliver clean air in spaces up to 120 cubic feet, making it ideal for small to medium-sized rooms. This air purifier uses ultraviolet light to kill airborne bacteria, and a True HEPA filter with a photo catalyst to capture microscopic allergens such as pet dander, smoke, and dust mites, to ensure a clean and healthy environment. The 3-speed fan is adjustable with manual push-button control. Digital controls make the unit easy to operate and to adjust to lower speed and noise level in Sleep mode.  An indication light alerts you when the air filter needs to be replaced.