Shag and Craig are right, it's for the castle sidewinder ESC to use it for brushed. If it's over a 19 Turn motor, you need to have all 3 wires for the motor going to the negative motor terminal.
The problem is, the Sidewinder has the wires hard-fixed, not on mounting posts that I could easily de-solder. So, if I splice it 1/2 way down one of the wires, and I want ot go to brushless later, I will have to shorten all of the wires to the point where I spliced it. I guess that's not such a big deal though.
I'll give that a go. Thanks.
BTW, I don't want to go brushless because you can't use them for competition in NZ, which I plan to start racing in next year. Also, they are VERY expensive here.