For an upcoming family event, I wanted a powerful, quiet #CorsiRosenthalBox that could be collapsed to carry in the car. I started with a @robwiss format of 9 Arctic P14 PC fans with 4 20x20x1 Filtrete MERV13 filters. I used Filtrete 1900s which are very similar to his Filtreet 2200s, so I'm hoping for performance similar to what he measured (556CFM CADR, 44.5dBA noise). Collapsed it's 21.5x21.5x5.5" and weighs 17 lb. Expanded its 24.2" high. With a little practice, it takes about 6 minutes to expand with NO TAPE. (Re-collapsing is faster.) In a 300 sqft motel room, running from a 125VAC-12VDC 2A supply, it should clear 90% of the aerosol in 10 minutes with about 14 ACH! The event room was big, so it can't do much overall, but it was next to our table running on a 6.5AHr LiFePO4 battery [6.5AHr/(9x.15A)=4.8Hr] so it prolly helped, + we masked when not eating. After 6 days at least 2 of the ~60 attendees have tested + but we're still healthy.