holmes d filter

Filter D replacements are offered mainly in two types: true HEPA-style replacements (often paired with activated carbon pre-filters) and separate wick-style replacement filters marketed for Filter "D".

Product descriptions state these replacements target common airborne allergens such as pollen and smog. HEPA-plus-carbon packs additionally claim to remove many household odors and to capture particles down to 0.3 microns (up to 99.97% efficiency as listed).

Compatibility listings commonly show Holmes air purifier HAP-series models and Holmes humidifier HM-series models as requiring a Filter "D".

HEPA-style replacements are described as removing up to 99.97% of airborne particles as small as 0.3 microns, and product details also list typical captured allergens like pollen and smog.

Activated carbon pre-filters are included alongside HEPA filters to help eliminate many household odors and chemical smells and are described as helping to extend the HEPA filter's life.

HEPA-plus-carbon replacement packs show explicit counts—for example, listings state 4 HEPA filters together with 8 pre-filters included in the same package.