The threaded nipple d25 mm with a 3/4″ male thread is a small PVC-U adapter fitting for the direct connection of 25 mm diameter pipework to threaded fittings or devices with a 3/4″ female thread.
It is used in chemical dosing stations, inline heaters or smaller circulation pumps with inch-sized connections, where using two separate parts would unnecessarily complicate the installation.
PVC-U guarantees chemical neutrality against the acids, disinfectants and algicides commonly found in pool circuits, so the nipple retains its tightness even after years of operation.
