- Compatibility and fit: Fits MORENTO HY4866 air purifiers (HY4866 model) and HY4866U; also compatible with YIOU M1 air purifiers and WESTHEY HY4866 air purifiers. Not compatible with other brands. Please check the model before purchase. - 3-stage filtration: Nylon pre-filter (electrostatic cotton) captures hair, lint, and pet fur; H13 TRUE HEPA filter removes 99.97% of particles 0.3 microns; high-efficiency activated carbon filter absorbs odors from pets and cooking fumes. - Multi-stack filtration technology: Honeycomb shaped activated carbon layer provides better purification and longer service life. - For best performance: Designed for MORENTO HY4866 with dual side air inlet. Easy to replace and disposable without tools. Replace every 3-6 months for peak performance. After replacement, press and hold the switch for 5 seconds to restart. - Valuable package: Includes 2 x HY4866 True HEPA filters and 2 x extra pre-filters. The electrostatic pre-filter traps larger particles, reducing load on the main filter and extending the life of the HEPA element. - Use scenarios: Ideal for homes with pets to reduce dander and odors; useful during allergy season or pollen periods; suitable for kitchens and living rooms to improve overall air quality.