With regard to the PRO-91 9v 300ma Negative Tip p/s, for starters, I'm desperately looking for one, mine just puked, and it is what I host my feed here on RR with, if you can help please advise. I have tried RS itself using the cat#'s in the manual which seem to be non-existent, and trying an inet search yields nothing but positive tips or full size neg. Second, it is not the full size negative tip, but not the mini either, it's some middle size, does anyone know what size or if this has a special name.