The threads on my AGA are the right I.D., maybe even a bit too wide, but they are not as tall as they should be (the O.D. is too narrow). So, it makes them very easy to cross-thread, and on some of my tube mods it won't even screw on at all. I would be careful with this one, because the weight of the AGA also creates a lot of leverage against that tiny 510 connection.