Tesnit BACF 4000 Asbestos 1mm 2mm 3mm Sheet Gasket BACF 4000 is a premium grade quality gasket material. Tesnit Bacf 4000 Packing is based on a combination of aramide and carbon fiber, specially selected fillers, additives and elastomeric binders. With careful selection of components, this material is free from harmful nitrosoamines (certified by MRPRA) and fibers that are harmful to human health. In addition, when applied at high temperatures, no significant emissions of harmful degradation products have been detected. Apart from the improved sealability resulting in a notable reduction in fugitive emission levels, the new material also has excellent creep-relaxation as well as excellent chemical resistance especially in alkaline media.