Flexible pipes not of metal and non-metallic pipes for plumbing purposes; plastic flexible pipes; junctions not of metal for plastic flexible pipes; valves of rubber or vulcanized fiber; non-metal pipe joints; pipe insulation for flexible pipes not of metal; inner linings made of non-metal fabric and sealant for plastic pipes; plastic junction compounds for pipes; non-metallic casings for pipes; non-metal hoops for pipe joints; gum rings for uses as coupling joints for pipes; plastic sheets, ...