There's actually a bit of an optical illusion going on there, it's actually a female Stabilizer side-mounted to the valve, with an ASA-to-NPT plug for macro from the vertical ASA. Maybe easier to just show the other other side:
Zombie Defense Force, Local 42 #61 "Darwin" IT'S TIME TO TOSS THE DICE___MAKE THE OTHER SIDE PANICKY DarwinZDF42
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"Integrity is doing what's right, even if nobody is looking." My MCB feedback