3M Filtrete Eureka / Sanitaire HF-9 / HF-9 Ultra Allergen Vacuum Filter - 1 filter Nullify Imported Fits vacuum models EUREKA* Boss* Widetrack, Whirlwind* and Whirlwind Lite* (4100, 4300-4600, 5180, 5190, SC4180, SC4500 Series) Uprights. Ultra Allergen filters help trap 99% of airborne pollutants 1 micron or larger including household dust, dust mite debris, grass and ragweed. Vacuum Filters should be replaced every 30 to 60 days for optimium performance. All vacuum brand and model names are registered trademarks of vacuum manufacturers.