... insulation,heat preservation, fireproof,sound absorption Fiberglass Needle Mat are of superior heat insulation,heat preservation,fireproof,sound ... structure and shell body of the metal and pure plastic wooden materials, reduce the needed driving force, save ... .0370.0480.0580.0760.0940.1120.16Fibreglass needle mat Absorption and Vibration Property Hz125250500100020004000sound absorption coefficient0.320 ...