1. Carefully check your model to ensure that this is the correct filter for your air purifier. This filter is suitable for air purifiers of models such as Core 400S and Core 400s - RF, and its working effect is the same as that of the original filter of the device. 2. High cost - effectiveness: The super - value set can save you a large amount of cost for your annual air purification needs. It has a higher level of filtration performance and can be used for a long time. It is recommended to replace it every 6 - 12 months. Using an old filter will reduce the efficiency of the air purifier. 3. H13 True High - Efficiency Particulate Air (HEPA) technology: It uses a higher - grade true high - efficiency air filtration material with a 360 - degree filtration function, which can capture 99% of particles with a diameter as low as 0.3 microns. Improve the air quality in your room, make your breathing and sleeping easier, and avoid runny noses and sneezing. 4. Efficient odor removal: The activated carbon filter can filter out bad odors and smoke, including volatile organic compounds (VOCs), tobacco smoke, cooking odors, and pet odors, significantly reducing indoor odors and creating a pure air environment. 5. Easy to install: Suitable for Core 400S, no need to cut the high - efficiency air filter. You can replace the old filter without other tools, saving your time and being very convenient to use. 6. Color: White 7. Material: Composite material 8. Package content: 1 piece 9. Only the above package content is included, and other items are not included. 10. Note: Light reflection and different displays may cause the color of the item in the picture to differ slightly from the actual one. The measurement tolerance is +/- 1 - 3 cm.