Assuring Perfect Fitting: With our true HEPA filters, assure perfect fitting and compatibility with for HY4866 and YIOU M1 air purifiersHowever, ensuring the model before purchase is recommended. Innovative True HEPA Filtration: Adopts a honeycomb activated carbon structure improving purification effects and prolonging the service life. This improved design sustains optimal performance and efficiency of your air purifiers over extended periods. Economic and Enduring: Our pack includes 4 filters compatible with for HY4866 air purifiers exhibiting a lifespan of 8800 hours. For maintaining ultimate purification performance, replacing filters every six months is advised; although it depending on usage and environmental conditions. Quality Promise: While extending the durability of your air purifiers, we also prioritize the quality of our HEPA filters. Ensuring they are of high-quality, we them to comply with HEPA testing standards 's safety. Health and Well-being at the Forefront: a cleaner and healthier environment and your loved with our premium quality filters. With certified HEPA technology, our filters trap airborne particles ensuring a space for all. Colour:black+white Material:composite materials Package Contents: 4 x Air Purifier 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.