The HEPA is a highly efficient particle filter with a 99,2 % filtration @ 0,4 microns. Regular filters are usually able to filter only 1-2 microns. The filter is made from fibreglass and is folded multiple times to improve filtration. The securely affixed microfilter does not stand in the way of fluent airflow which enhances the performance of the filtration system. If the filter were only one layer, the efficiency would be zero. The folded design allows it to contain the smallest dust particles and thus filter the air in your woodshop. PFlux 1 is fitted with a clogging indicator signalled by an LED light of the control panel. You can create a vacuum in the HEPA by connecting the main container with the microfiltration cap using a hose, this technique cleans the insides of the machine. Make your maintenance more efficient blowing out the filter from the outside during cleaning.