TRUE HEPA H13 FILTER WITH ADVANCED 4-STAGE FILTRATION SYSTEM: 4-stage filtration (Pre-filter, Ture HEPA Filter, High-Efficiency Activated Carbon Filter, and Net Filter) can effectively capture 99.97% of particulates as small as 0.3 micros such as allergens, pet hair, dander, smoke, mold, odor, and large dust particles. This 4-stage air purifier can improve indoor air quality, freshen air at home, and help you breathe better. HIGH EFFICIENCY AIR PURIFIER: With a CADR rate of 100 CFM (170 m³/h), this air eliminator can circulate an entire room's air 3 times per hour in spaces up to 240 sq.ft (20m²). Unique size and contemporary design make the RNEPHO air purifier perfectly suited for small or medium sized rooms like living rooms, bedrooms, kitchens, offices, and dorms. 3 FAN SPEEDS WITH SLEEP MODE AND WHISPER-QUIET OPERATION: Choose from low, medium, or high fan speeds according to the air quality. Operates quietly at 26dB during sleep mode so your air is purified while you sleep undisturbed. 3 TIMER OPTIONS WITH NIGHT LIGHT: This odor eliminator provides a timer option that allows you to set an auto-off for 2 hours, 4 hours, or 8 hours, helping you save money and energy. There are two light modes: night light and colorful gradient. The light is gentle and dim. FILTER REPLACEMENT INDICATOR: The convenient filter replacement indicator will flash to remind you to replace the air filter. The air filter usually should be replaced every 6-8 months depending on the air quality in your area and how often you use the purifier.