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![O2 Flow Replacement Filter / True HEPA + Carbon Filter - 4 Stage HEPA H-13 Carbon Filtration](http://purespadirect.com/cdn/shop/files/o2-flow-replacement-filter-true-hepa-and-carbon-filter-4-stage-hepa-h-13-carbon-filtration-lp-267851-1_60f9f403-acd2-4876-84b5-b3dc58486d21_20x_crop_center.jpg?v=1703734986)
O2 Flow Replacement Filter / True HEPA + Carbon Filter - 4 Stage HEPA H-13 Carbon Filtration
O2 Flow Replacement Filter / True HEPA + Carbon Filter - 4 Stage HEPA H-13 Carbon Filtration. Replacement filter for the O2 Flow Electric Face Mask. 4-Layer Super-Strong Composite Filter for Air Purification - HEPA combined filter four-stage filter system (HEPA filter, activated carbon, sterilization membrane, medical non-woven fabric), which efficiently removes fine particles in the air with a diameter less than or equal to 2.5 microns (equivalent to 1/24 of human hair) Particulate matter, such as viruses, bacteria, exhaust gas, formaldehyde, pollen, dust, allergens and other harmful substances, the purification efficiency is up to 98.8%, which really plays a defensive role in blocking harmful substances from entering the human respiratory tract and damaging the respiratory tract.