Breathe in fresher air using the 3-in-1 True HEPA replacement filter from Pure Enrichment. Enjoy improved air quality as the premium 3-stage filter safely cleans the air in any home or office. Our filter is designed to work with the Pure Enrichment PureZone Air Purifier (sold separately). <br><br> Each of the three layers of this filter provides a unique level of cleaning: <br><br> <b>Pre-Filter:</b> Captures initial dust and allergen particles. <br> <b>Activated Carbon Filter:</b> Absorbs formaldehyde, benzene, and other noxious gases. <br> <b>HEPA Filter:</b> Captures dust, smoke, pollen, and other allergens. <br><br> For optimal performance, we recommend replacing your unit's air filter every 6 months.