... -320 g/m2 3.Thickness,5-25mm Supply Air Conditioning Filter Media , Synthetic FIber Features1.Using polyester, polyamide, nylon, etc. chemical synthetic ... . The integration between the fibers is closer, and the fiber is not easy to shed.4.Low flammability, fire resistance ... filtration of fresh air, pre-filtering prior to medium-efficiency filter, as well as filtration of return air in central air ...