I found out the powerhead for my 413 Royal canister uses the same plugs and sorta fits the metal pipes my C9 has when I was getting it running and it needed a new belt and maybe motor in the head. It worked well enough if I could keep them plugged together but I got a belt and that was all it needed after the main motor was replaced. I spose it works but hard to say if it is useful for anything but it is fun to try oddball parts you have around to see what you can cobble together and make work or possibly make a Frankenstein improvement.