I've got an AP tank and reels, as well as one Paterson reel. The Paterson reel works in my AP tank. I suspect (but don't know for sure) that AP reels would work in a Paterson tank. Thus, if you've got a Paterson tank and reels that don't do 127 format, you could try an AP reel without buying an AP tank. (That said, I've not checked any of those reels for 127 compatibility, so I can't verify Brac's claim that the AP reels support 127 and I don't know whether or not the Paterson reels support 127.)