... 3.free of maintance 4.singele used 100g moulded non-woven dust mask,respirator protection,canister filters 1.Description: ... Feature:1.Non-Woven Fabic:PP Non-Woven, Active Carbon,Filter And Needle Punched2.Made With Non-toic,Non-Allergic And Non-Simulating Materials, ... Engineering,Minning,Petroleum,Shipbuilding,Metallurgy,Coal,Environmental Sanitation,Paint Industries,Automobile Manufacturing,etc