Insulating materials; tubing, sheets, sleevings, wrappings and articles made wholly or principally of rubber, synthetic rubber or plastics materials, all for insulation, protection, jointing, sealing or splicing or for use in the assembly of electrical, telegraphic or telecommunications apparatus or instruments or for use in the assembly of wire, cables or optical fibres; sealants; mastics; sheets, sleevings and wrappings, all lined or coated with sealants, mastics or adhesive substances.;