... ,PP,Acrylic,PPS,Nomex,P84,PTFE,FMS,Glassfiber Felt Material: Polyester fiberWeight (g): 500 Thickness (mm):2.0mm Air Permeability (L ... them with singeing, calendering, heat setting, Teflon coating and membrane. polyester needle felt adopt nonwoven workmanship, with the property of stable ...