Corsair will tell you that they are only designed to work on their PSUs (not just the AX series).
So I would not use them on a PSU sold by another company unless you can somehow be 100% sure they will work.
So how do u think they do it? Just put a notch in the side of the connector so u can't plug it in on a normal rectangle connector? I can't see them being very hard to make universal, but I'm also sure corsair would make it hard to do so...