Plug-in fittings

A plug-in fitting has no socket on one side but a smooth stem, exactly as thick as a tube. You click that stem into an ordinary push-in fitting. That way you build two fittings together without a short piece of tube in between.Most of the use is in reducing. An 8 mm stem with a 6 mm socket puts a thin tube on a thick port, with no separate reducer and no rework on the port itself.