Arm & Hammer air filters are designed to trap airborne particles like pollen, dust, pet dander and a variety of other common airborne allergens. Like many Harm and Hammer products that are designed to clean, this filter is designed to help "clean" the air in your home by reducing airborne particles and reducing odors. The Arm & Hammer Maximum Allergen and Odor Reduction air filters maximize odor reduction with three powerful built-in ingredients. First, Arm & Hammer baking soda has been a trusted odor fighter since 1946 and it neutralizes odors on contact. The filters also contain Oguard II a proprietary odor reduction ingredient that is highly effective at reducing a wide range of odors. Lastly they have built-in carbon granules with have a large capacity for absorbing odors. The electrostatic, pleated filter has a Merv 11 allergen reduction performance and lasts up to three months. From the Manufacturer Arm & Hammer air filters are designed to trap airborne particles like pollen, dust, pet dander and a variety of other common airborne allergens. Like many Harm and Hammer products that are designed to clean, this filter is designed to help "clean" the air in your home by reducing airborne particles and reducing odors. The Arm & Hammer Maximum Allergen and Odor Reduction air filters maximize odor reduction with three powerful built-in ingredients. First, Arm & Hammer baking soda has been a trusted odor fighter since 1946 and it neutralizes odors on contact. The filters also contain Oguard II a proprietary odor reduction ingredient that is highly effective at reducing a wide range of odors. Lastly they have built-in carbon granules with have a large capacity for absorbing odors. The electrostatic, pleated filter has a Merv 11 allergen reduction performance and lasts up to three months.