AEM’s DryFlow Synthetic filter eliminates the hassle of re-oiling after cleaning and has better filtration and dust trapping capabilities than any other performance aftermarket filter. Our unique non-woven polyester element filters out 98.6% of airborne dust in initial efficiency (99.4% cumulative efficiency), and filters down to ONE MICRON of particulate! For comparison, a human hair is about 100 microns thick. This improved efficiency translates into longer engine life by keeping more ring- and seal-eating dirt out of your engine, with no degradation in engine power compared to oiled air filters. It also means you won’t have warranty issues at the dealership because you never have to worry about over-oiling the element and having the filter oil damage your vehicle sensors.