The 3M™ Cartridge/Filter Holder 7586 is designed to be used with the 3M™ Half Facepiece Reusable Respirators 7501, 3M™ Half Facepiece Reusalbe Respirator, 7502 and 3M™ Half Facepiece Reusable Respirators 7503. It includes two inhalation valves and one exhalation valve.The 3M Cartridge/Filter Holder 7586 is to be used with compatible products. Replacement part can extend respiratory equipment service life.