... stander length:5m or 10m4,Main color: yellow,red,orange .white,black,green ect.5,Character: enduring high temparature,acid,alkali ... such as tunnel, basement, ship building or welding, laboratory ,air-conditioner,engine room, the municipal conduct engineering,fire-fighting to ... ventilate or exhaust waste air,dust to supply fresh air.keep more savely and effectively during working. ...