A telephone service cable which runs from a distribution cable to a subscriber's premises or to a pay station is another link in a buried communications system having a water-resisting capability. A spirally quaded core comprised of individually insulated conductors is advanced through a bath of a flame-retardant, water-resistant composition prior to enclosing the core with a jacket. The interstices in the core and between the core and an inner jacket are caused to be filled with the composition which comprises a liquid system and a solid system. The liquid system includes a chlorinated paraffin while the solid system includes a polyvinyl chloride resin and a chlorinated polyethylene. An epoxy stabilizer and a phosphite stabilizer may be added to prevent thermal degradation of the filling composition.