Choosing high-quality filters is based on the three filters manufactured in the United States, each of which is made of Flemish precision air. These filters are provided by the same hospital system, nuclear energy facilities... and even NASA. Flanders is the largest filter manufacturer in the country in the United States and well-known home improvement stores that supply high-end residential filters. Our filtereasy filters are actually the same ones that Flanders found in these stores for your filters (our actions mean they are exactly the same). The only difference is packaging. Oh, and with the price, of course our costs are reduced.