PM2.5 Replaceable Filters for Various Face Masks. 5th layer of spunbond cloth filters out all kinds of harmful substances. Filter Size: 12 x 8 cm. PM 2.5, best to protect your mouth and face from Dust, Haze, Germs, Allergies, Smoke, Pollution, Ash, Pollen, Gardening, Crafts, etc.
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