1. :115115 HEPA replacement filter A size 21 fit perfectly with Winix PlasmaWave Air Purifier Models 5300-2, C535, 6300, 5300, 6300-2, P300, AM90, 9000, 5000, 5000B, C909, 9800. Please check your purifier model before making an order 2. : The 5300-2 H13 Medical Grade True HEPA Filter compatible with winix air purifier filter replacement can attach up to 99.97% of particles and impurities as tiny as 0.1 microns including dust, pollen, pet dander, pet hair, and more. Effectively improving the air quality for you 3. : Our 115115 Carbon Filters compatible with winix c535 replacement filter can clean up large particles, extend the life of the True HEPA filter, and take in odors in the environment such as volatile organic compounds(VOCs), tobacco smoke, and cooking odors. It's the ideal choice for pet owner and cooking lovers 4. : Our 6300-2 air filters replacement are made of high-quality non-woven fabric, constructed with premium HEPA 13 to greatly improve the performance of your 6300 filter replacement. We adopt advanced lower energy consumption and lower density structure technology, higher efficiency and less pressure to ensure maximum filtration 5. : Without using the carbon pre-filter, it's recommended to replace the 115115 HEPA replacement filter A size 21 every 6 to 8 months. But when used with carbon pre-filter it can extend the replacement time of the true HEPA filter to 12 months.The carbon filter ensures long life for your 115115 true HEPA filter 6.- : Our c909 replacement filter set Includes 4 carbon pre-filters + 1 true HEPA filter for year-round use, recommended replacement carbon pre-filter once every 3 months, and change the True HEPA Filter once every 12 months. They are an efficient investment for your family. Easy to replace, no tools required. Simply take out and replace it from your machine unit when needed