Replacement for Honeywell 21500 Air Purifier Filter Specifications HEPA High-efficiency Particulate Air and low-maintenance home air cleaner Filter. Captures airborne mites, mold spores, pet dander, smoke and dust.Efficient upto 99.97% at removing particles as small as 0.3 microns from the air that passes through the filter. Surround Seal filter technology prevents dirty air from leaking around the filter. Replace every 1-3 years depending on use and environmental conditions. Replacement for 11500, 11502, 11520, 11525, 11526, 11528, 11573, 17200, 17201, 17205, 17210, 18000, 18150, 18153, 18155, 18159, 26500, 50150, 51500, 61500, F112A6003 Approximate Dimensions 6 1/4 H x 9 1/4 ID x 14 1/2 OD. Description HEPA High Efficiency Particulate Air The HEPA high efficiency particulate air Air purifier filter provides you with the best air purifiers for mold spores, odor, pets, pollution, etc.Air purifier filters provide you with a simple way to find all the air purification you need. Key Uses These Air Purifier Filters can assist in creating a cleaner and altogether healthier breathing experience in the home or work environment. Cleaners and Air Purifiers captures microscopic particles and allergens that can be ruinous to the quality of air you intake. These are also capable of removing allergy provoking dust, pet dander, pollen, smoke and mold spores from the surrounding indoor air. Excellent Breathing Experience The Replacement Air purifier filters keep your family healthy and your home clean.With the best of Air purifier experience and Breathe only the cleanest air.The high purification capacity of the HEPA filters purifies the room instantly.Nothing’s more important than keeping your family breathing healthy air and keeping your home clean . Composed Of HEPA filters are assembled in a mat of randomly arranged fibres.It consists of fibers which are composed of fiberglass and has diameters between 0.5 to 2.0 micrometers.Factors affecting its functions are fibre diameter, filter thickness, and face velocity.The air space between HEPA filter fibers is typically much greater than 0.3 μm.