... as benzene,formaldehyde and other pernicious gases.Used in hospital,food industries,electronic industries,paint factories.Size: 95* ... as benzene,formaldehyde and other pernicious gases.Used in hospital,food industries,electronic industries,paint factories.Size: 95* ... as benzene,formaldehyde and other pernicious gases.Used in hospital,food industries,electronic industries,paint factories.Size: 95* ...