Item Blank #4: KN95 Mask - Four Layer Construction with Polypropylene Inner Layer. FDA Approved. Domestic Stock 200 unit MOQ.Light and breathable, 4 ply layer face masks with added protection of an inner layer of high density, melt blown polypropylene. FDA Registered 95% filtration for particles larger or equal to 0. 3 microns 4 Ply construction, including inner layer of melt blown polypropylene One size fits all with comfortable, form fitting design Adjustable nose bridge and elastic ear loops Complies with China Standard GB2626 2006 and European Standard EN149: 2001+A1: