The washable air filters by HEPA and the regular air filters by HEPA.
I work for a local heating and air conditioning company in my area. I have been for the last 3 years and I love it! Recently they had a bit of a dilemma they had to make a choice on. They sell air filters for central heating and air conditioning systems of course, and they wanted to narrow it down to only sell one brand of air filters for central heat and a/c units. The upper management said it was going to be better for business and will gain the financial support of whichever brand name company of air filters we decided to go with. So the entire company took a vote based on experience. Even us heat and air conditioning workers were included and required to vote. It was really unlike anything I had ever seen or experienced before. In the end, it turned out that the vote went for HEPA brand air filters. Both kinds. The washable air filters by HEPA and the regular air filters by HEPA. All other brands of HVAC air filters were phased out and would no longer be sold here once they were sold out. I don’t exactly get the concept of all this personally, but if it is going to bring outside funding to help keep our heat and a/c company going no matter what, I can completely understand and advocate for an exclusive brand of HVAC air filters. I am glad HEPA was the winner. Because HEPA seems to be the best and leading brand in air filters on the market today!