http://www.mcmaster.com/#compressed-air-filters/=96eufz
years ago at work they used this style filter, to me the main advantage was that for replacement cartridges you use rolls of toilet paper. i can think of little else that would act as such a good filter and be so economical to replace. there is a high up front price for the cartridge holder but if you do a lot of painting and air tool use over the years it would pay for it self. listed under super ultra-fine submicron air filters