raw or semi-worked rubber, gutta-percha, raw or semi-worked gum, asbestos, mica; plastics in extruded form for use in manufacture; packing, stopping and insulating materials for lining, sealing or repairing a damaged pipe, made wholly or predominantly of plastics material, elastomeric material, nitrile rubber or polyvinyl chloride, and parts and fittings therefor; flexible pipes, not of metal; pipes, pipe couplings, pipe adapters including adaptor couplings for coupling pipes of different siz...