These flashback arrestors are a safety device mandatory in an flame station system where the brazing torch is not equipped with a FLASHBACK ARRESTOR.
Please note, you will never use those FLASHBACK ARRESTORS with a torch already equipped with it.
This model is a female/male one-part piece where you will connect a HOSE on the male side and the GAS PRESSURE REGULATOR on the female side GPRH( gas pressure regulator to hose) to ensure its installation into a system.
When sold, it comes as a 2-piece set, one for the Oxygen, and one for the Acetylene to ensure the connection and it is most likely to remain in the same system.
Please note that these references are delivered with their own HOSE CLAMPS set.