Hunter 30906 replacement HEPA filter for Hunter models with 4-in-1 Total Air Purification system. This filter is protected by Microban antimicrobial protection that inhibits the growth of bacteria, mold and mildew that can cause odors and adversely affect filter performance. It removes 99.9-percent of common household airborne allergens including dust, smoke, pollen, pet dander and dust mites from the air that passes through the filter. Easy to install genuine Hunter part.