electrical insulating materials and substrates, namely, fabrics, fleeces, foils, and paper impregnated or coated with hardenable synthetic resins for insulating purposes; plastics in extruded form for use in manufacture; semi-finished products made of plastics and fibre fabrics, non-woven fabrics or knitted fabrics in the form of films, sheets or moulded parts; Plastic fibres, other than for textile use; insulators and insulants for electricity, heat, and sound