UPDATE: Well Here's Another New One (at least to me!)

Maybe try shaving the misaligned ridge on one on the plugs, so that it will plug into the female plug/socket.  Just one time, and briefly; they may not be pinned the same even when you align them in the suspected correct orientation.  Could cause damage.

I would use ohm meter to read it out to see what is up.  Manufacture may have messed up making it.  G

Yah I wont try it at all before pinging it to see how the connections line up. Wonder how many more are out there like this?? Think I’ll give MTH parts a call Monday and see what they can tell me.

That will be interesting Rod, as I didn't know you could just pick-up the phone and talk to Don and the other boys at Spare Parts.

If you get through, please let me know the number, and I'll see if Don can "Whats App" me here in Australia.

Peter.....Buco Australia.

You are right Buco, there is no handy published phone number to call MTH Parts. Email only. But they respond pretty quick with on the spot answers.

After several go rounds back and forth it turns out that what I thought was a new revised part is actually the same pass-thru tether that has been around a few years now. A PS2 slave kit I checked has the exact same PN and design cable with it.

The problem turns out to be that the early PS2 5V sets used a different plug with the ribs low on the side like in the picture I posted. So to use a new pass-thru cable with it you would have to invert the plug end; ie TOP side down, which would be confusing at best. Also the socket on the other end has the mounting stud holes set way higher than the socket body. So it would interfere with the coupler if inverted.

Bottom line is these pass-thru's are NOT compatible with older PS2 sets. The design may have changed when the 3V boards came out, not sure.