... introduction:*Fabric: Soft non-woven cloth, soft non-irritating to skin*The filter layer is made of high efficient melt ... water repellent and air permeability*Maintenance/cleaning free, folding,convenient to use*Recommended applications: Hardware, plating, mining, chemical, sterilizing, ... C) We introduced”TSI 8130 Automated Filter Tester” from USA to test our mask during the whole producing process,so ...