I haven't actually acquired this compressor yet - one was offered to me on trade, and supposedly the nut is missing from the output jack. I know that they the jacks on these are soldered directly to the PCB so it's something I'd want to get fixed asap.
So, I can see enough from the image searches to tell that it's not your standard hex nut that you'd see on standard 1/4" jacks - which opened up the possibility that it's another type of proprietary fastening system...I've seen jacks where the outer fastener is actualy the "bolt" part of the system, etc.
But if it functions as a normal hex nut would, that's looking good enough to me
