ventilation air duct(air hose) for mining: diameter: 600mm length:10m The feature of Yecheng brand fiberglass fabric ventilation duct:Yecheng brand has the feature of flame resistant,anti-statics,small windage,low air leakage ratio,high intensity,convenient usage,long service life and so on. It is applicable to downhole coal-mine,metallurgy,tunnel,subway and so on,executing MT164-1995 standard. ...