Excellent filter for removing Chemicals and. Heavy smoke in high traffic areas. High capacity collector for most Airborne. 12 sets in a case will clean 12 Purifans. This item is in the category "Home & Garden\Home Improvement\Heating, Cooling & Air\Indoor Air Quality & Fans\Air Filters".The seller is "purair_23" and is located in this country: US. This item can be shipped to United States.