1. Air Filter Replacement for HY4866 2. Replacement Filter for HY4866 Air Purifier: air purifier replacement filters guarantee certified fit and maximum filtration.Off-brand filters frequently fail HEPA testing standards,fit incorrectly,reduce efficacy,and may cause damage to your air purifier 3.Upgraded Activated Carbon Content and Electrostatic Cotton: Different from the standard version,the enhanced filter is covered with a layer of electrostatic cotton and the activated carbon content in the filter is higher to intercept more large particles and pollutants in advance, absorb some odors.Higher filtration efficiency and longer filter life 4.Two-piece package: This package contains two Enhanced version air filters.The life of the HY4866 air purifier filter is generally 2200 hours,Recommend you to replace the filter each 3-6 months, Please replace the filters according to its life. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.