1.PERFECT FIT: 14 replacement filters exactly designed for MA air purifier 14/14W/14B models.The package includes 2 filters, and it's recommended to replace the filters every 2,500 hours or 3-4 months. 2.3-IN-1 FILTRATION: 14 replacement flters for MA are made of 3-in-1 filtration systems including Nylon Pre-Filter, H13 Medical Grade True HEPA Filter, and Activated Carbon Filter. 3.HIGH-EFFICIENCY: The 14 True HEPA filter for MA are capable of attaching 99.99% of airborne particles as small as 0.01 microns, and the carbon filter helps you solve the problem of unpleasant odors and gases. 4.COST EFFECTIVE: Package includes 2 Pack 14 filters. Fully meet your needs for the replacement of 14 filter, with premium materials and advanced technology, ideal solution for homes with pets, smokers, open layout kitchens.