Most listings show a filter measuring 1.2 x 10 x 4.6 inches (10 inches high × 1.2 inches wide × 4.6 inches deep); one listing offers a larger option at 9 x 6 x 10 inches.
Product details list polypropylene filter media, activated carbon, and a preliminary fiber pre-filter as the materials used in these replacement filters.
Product details recommend replacing the air purifier filters every 6 months to maintain effectiveness and efficiency.
Installation is described as easy: remove the old filter and insert the new one with no additional tools required.
Product descriptions explicitly state these are not Holmes OEM parts and that use of the Holmes name is for compatibility demonstration only.
Descriptions state the activated carbon layer targets smoke and household odors from cooking, pets and chemical sources.