MAINTAIN YOUR UNIT: Use MA-25 replacement filters (B0859841GP) to your MA-25 air purifier operates as it should, keeping the air inside your home, apartment, school, or office clean. FILTER SET: One replacement filters (two filters total) for Air purifier model MA-25 only. This unit has a filter on each side. Both filters must be replaced at the same time. HEPA H13 FILTRATION: Trusted to remove 99.9% of harmful particles including allergens, odors, VOCs, smoke, pollen, pet dander, dust, smog, contaminants, and more down to 0.1 Micrometres in size. Captures finer particles than HEPA H11 (0.3 Micrometres). 3 : Multi-stage filtration; pre-filter traps pollutants, HEPA H13 for fine particles, and active carbon to remove odors. Perfect for smokers, pet owners, allergies, volatile organic compounds (VOCs), and cooking smells. LIFETIME: Each easy-to-replace filter set lasts 3-4 months or 2,500 hours, whichever comes first. Only 3-4 filter changes per year means lower maintenance and more cost savings. Colour:white+black Material:plastic Size: 24.2 x 17CM Package Contents: 4 x HEPA Filter Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.