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; flexible pipes, tubes and hoses, not of metal; expansion joint fillers, fillers for panel joints, concrete, fabricated slabs; fillers for joint packing; insulating fillers; flexible fillers