Bulk Filter Brand Filters PREMIUM REPLACEMENT FILTERS MADE IN THE USA. 1- roll 24 wide x 25′ long of bulk filter media. The carbon is impregnated into a non-woven polypropelene filter media, and is approximately 1/4 thick. Exact thickness can vary based upon manufacturing process, however the same amount of carbon is present regardless of exact thickness, air flow is not affected. Track Page Views With. Auctiva’s FREE Counter. This item is in the category “Home & Garden\Home Improvement\Heating, Cooling & Air\Indoor Air Quality & Fans\Air Purifiers”. The seller is “bulkfilterstore” and is located in this country: US. This item can be shipped to United States, Mexico, Canada, Bermuda.