6650 Polyimide film/polyaramide fibre paper flexible laminate (NHN) is a three-layer flexible composite insulation paper in which each side of polyimide film (H) is bonded with one layer of polyaramide fibre paper (Nomex). It is the highest grade electrical insulating material, the thermal class is H, it is also called 6650 NHN, H class insulation paper, H class insulation composite,etc.