167 - Double Swivel Connection.
A versatile swivel fitting, useful for awkward applications where angles cannot be accommodated by adjustable angle fittings. The assembly is riveted together, although items can be supplied separately as 167M and 2 x 173F.
The through tube (vertical in photo) cannot be joined within the fitting.
Warning: To provide sufficient stability, whole structures must not be made from swivel fittings alone.