2 Pack 511 Replacement Filter Compatible With Blueair Blue Pure 511 Air Purifier, Is Designed For Optimal Performance | | [A Brand You Can Trust] Strict Production Process, From The Selection Of Raw Materials To The Professional Operation Of Production, Ensures The Quality Of The Filters And Provides Health Protection For You And Your Family! We Deserve Your Trust With The High- Quality Products And The Most Affordable Purchase Price | | [ Comparison] This Filter Compatible Air Purifier Filter Fit Perfectly With The Blueair Blue Pure 511 Air Purifier Filter Model, Just Like Those From The Oem.Hepa Remove Large And Airborne Particles, Including Dust , Activated Carbon Layer Reduce ? Tobacco Smoke | | [ Please Replace Regularly] To Keep Your Machine Fresh And Clean,For Best Results, Remove The Filter Once A Month And Clean With A Soft Brush Or Gently Vacuum. | | [ Easy Replacement]Top-Notch Quality Used For Maximum