Product: Fold high filter dust-proof mask with valve No.: HYKY-31 Material: Polyester + Filter Cloth+Non Woven Cloth Packing: 20pcs/box, 400pcs/Carton Description: 1. It is used for the protection from tiny dust particle. It is foldable and easy to carry. It is suitable for the environment of industrial and mineral field, electronic field, food processing and so on. 2. The design of valve is suitable for long-time wear in the wet and hot environment. 3. It has the effect of 95% dust proof and meet the stand of Ums NIOSH42CFR-84 N95.