Check the listing for details. Replaceable Face Mask Carbon Filter PM 2.5 (20 Pack)-IN STOCK USA. Color: Gray, Condition: New. Listed at 18.50 USD. PM2.5 Activated Carbon Filter 5 Layer Replaceable For Face Mask Cover Safety (BUY 20 ITEMS) Shipping from USA PM2.5 filters are shown to be effective in blocking the vast majority of airborne particulates, even the very smallest nanoparticles.PM2.5 filters are made from the same advanced materials used for advanced respiratorsA Mask + PM2.5 filter provides practical protection against airborne pathogens, dust particles, vehicle exhaust, woodwork, pollen allergies, and fumes.PM2.5 filters offer protection that's is practicalDisposable PM2.5 filters are flat, so they take up less space than standard respirators. They never lose effectiveness, and you can use them continuously for 16-24 hours, around 1 - 2 weeks of occasional use.*IMPORTANT*For sanitary reasons, all sales are final and cannot be returned.ShippingShipped with USPS First-Class Package with tracking numbers. We do not guarantee delivery time due to any unforeseen delays by USPS.Shipping TimeAll items are in stock and will be shipped to you within 24 hours of your payment being received, from ZIP Code 33432, USA Please note that items purchased on weekends or holidays will be shipped the following business day. We will ship to your address on EBAY only. Please correct your address on EBAY before ordering.