Unprocessed and semi-processed rubber, gutta-percha, gum, asbestos, mica and substitutes for all these materials; plastics and resins in extruded form for use in manufacture; packing, stopping and insulating materials; couplings and connectors for pipes, hoses and tubes, not of metal; flexible connectors for connecting pipes, hoses and tubes, not of metal; couplings and joints for pipes, not of metal; flexible pipes, tubes and hoses, not of metal; sealing rings; pipes, piping and tubes, not of metal; parts and fittings for the aforesaid goods.