... toxic gases as mustard gas, phosgene, sarin, etc. It features air tightness, anti-dust, Suitable for polluted places with such toxic ... gases as mustard gas, phosgene, sarin,etc. It features air tightness, anti-dust, waterproof, damp-proof, sand-proof,etc. It ... ): no osmosis, cold resistance, acid / alkali-resistivity, petroleum resistivity and hot air ageing