▶General particle replacement filter, compatible with Blueair Blue Pure Fan for large particles in the air, like lint, pollen, dust, pet dander ▶Package include 2 pack particle filters, part number 100930 ▶For optimal performance, we recommend replacing the filter every 4-6 months, depending on usage frequency and air quality ▶If you have any questions and issues about filter, please feel free to contact us Replacement Filter, 2 pack