1.More than 35 years Service life 2.Fireproofing, satety, non-toxic, easy installation and maintenance 3.sound insulation phenolic foam air ducting sheet is new generation environmental insulation material, when it is burnt, it has no smoke, it gives out non-toxic matter, the material is fire-resistance, insulated, water and moister resistant anticorrosion, anti-aging, sound insulation and energy ...