The PURIFAN Replacement Filters PAF-HEP PRO PAI are high-quality HEPA and charcoal air filters designed to clean 12 fans. With a MERV rating of 13, these filters are effective in removing allergens down to .3 microns. The filters are manufactured in 2025 and have a filter life of 6 months. PURIFAN Filters made by PurAir Filters since 2006, these blue and white filters are frameless and made with HEPA and charcoal filter media. The set of 5 filters in each pack will clean 12 fans, making it a convenient and efficient solution for maintaining indoor air quality. The cost is most reasonable as this small business has no high executive salaries to pass on to it's customers.