Telephone cables with polyethylene insulation, in plastic sheath, armoured TPPepB

1 Conducting cores - single-wire from copper soft wire.
2 Insulation - solid from insulating polyethylene.
3 Pairs - twisted from insulated cores of different colours. Pairs are twisted in five or ten-pair elementary bundles.
4 Core - twisted from elementary bundles of different colours.
5 Belt insulation - polyethylene terephthalate film, overlapped, polypropylene uniaxially oriented film, overlapped.
6 Shield - aluminium-polyethylene tape laid lengthwise. A tinned copper wire is laid longitudinally under the screen.
7 Sheath - polyethylene;
8 Protective cover - of two tapes of crepe paper applied with overlapping, layer of bitumen, two steel tapes applied with a gap, layer of bitumen, glass yarn, layer of bitumen, paraffin, chalk cover.