Filter-Monster branded replacement filter bundle compatible with IQAir PreMax, V5-Cell and HyperHEPA filters. Engineered to fit IQAir HealthPro Series air purifiers. Replacement PreMax pre-filter extends life of V5-Cell and HyperHEPA filters by capturing coarse and fine particles. Recommended to replace every 18 months for maximum efficiency.Replacement V5-Cell filter uses activated carbon to reduce VOCs (volatile organic compounds) and other harmful chemicals. Recommended to replace every 2 years for maximum efficiency. Replacement HyperHEPA filter uses True HEPA filtration to remove up to 99.97% of airborne particles as small as 0.3 microns in size including smoke, dust, pollen, pet hair and dander, mold spores and dust mite debris. Recommended to replace every 4 years for maximum efficiency. Package contains (3) replacement filters.