MY HUSBAND RECENTLY DIED OF COVID, HE HAD PURCHASED THESE FOR PAINT WORK ON AIRPLANES, MOST LIKELY.  HIGHLY USED FOR MANY DIFFERENT THINGS.  I have more filters etc. listed also among my items on 5superjs. Any questions please ask.

Please note that the filters are in great shape, but the mask has been sitting for a while, but the filters are brand new non-used and still good