PTFE needle filter bag Gram weight(g/m2): 508 Thickness(mm): 2.0 Permeability ... /m2/min: 2.4 Detailed Product Description PTFE needle filter bag Gram weight(g/m2): 508 Thickness(mm): 2.0 Permeability ... , quakeproof, heat-preservation, sound-insulated, filters, polishing. PTFE needle filter bag with cage filter