to add what has already been posted, there were 3 versions of the blue interconnect; Blue, Blue II, and Blue III.
after that Alex switched to another naming scheme; had one called microwave, but I don't recall where it fit into the line up. Alex was also one of the first to start using litz wire which is way better than any of the silver plated copper. At one time, I had my whole system wired in Blue II or Blue III. I think I have one 20 Ft pair still left.
If you want to be surprised, order some litz and make your own. You'll need a solder pot to tin the ends.