A connector for corrugated pipes or rods comprises a housing (2) having an open end (3) for insertion of a pipe or rod into a bore (5). A pair of resilient locking members or fingers (9) are formed in the housing wall and include projec­ tions (10) which extend into the bore (5). The projections are so shaped as to lock into a single valley of the pipe or rod cor­ rugations to prevent withdrawal of the pipe or rod. Also disclosed are methods of moulding the connector in which the fingers (9) are held and/or forced outwardly from the mould during withdrawal of a central core which forms the bore (5) to avoid damage of the fingers by the core.