... fibre air cylinder 5.Short delivery RHZK 6L 30Mpa positive pressure air respirator The RHZK series self-cbntained open circuit ... compressed air bresthing apparatus are used widely for fire-fighting,chemical industry,shipping,laboratory,mine,petroleum,warehose, ... .It can provide effetely respiratory protecting from toxic gases for fire-fighter,life-saver,rescue and operator who working ...