Tried it on my job site with full drywall dust, fine sanding dust combined with cobwebs. It fixed these shortcomings very well and made the bag plumper. Technology, most paper bags are very effective, and this HEPA is even better. OEM (Simplicitybag) could be better with thicker layers, but 'good enough' in my opinion. Regular package. Filtration 99.7% (2-ply paper bag) HEPA bag. Filtration 99.97% (cloth bag). I can't compare them to a home test so I have to rely on those numbers. HEPA fits my very old 7000 series very well. It also fits a 20 year old Kenmore vacuum too.