True H13 FilterThe filtration efficiency for 0.1 micron particles is as high as 9 9.97%, such as pollen, pet dander, which is strictly in line with the EU H13 standard and the US MERV 17 standard. . Unlike Other Activated Carbon Air FiltersUsing top quality coconut shell from Southeast Asia as raw material. It has the characteristics of developed pore structure, large specific surface area, strong adsorption capacity and high strength. Easily remove household odors, such as smoke, chemicals, and volatile organic compounds(VOCs). . Replacement recommendationIn order to maintain the excellent performance of your 411 air purifier, 411+ air purifier or mini air purifier, we recommend changing the filter every 6 months or so when it is used 24 hours a day. . Matching model& AttentionSuitable for 411 air purifier, 411+ air purifier and Mini air purifiers.Attention: Please check your air purifier when you buy it. If you have any suggestion ,please contact us and we will try Our best to let you satisfied. . Gift