Aha, it seems the reason for my confusion is that I used to have a Condor that was made before the spin loc tanks - so the tank threaded into the frame.My idea for my current build was to make the frame from 1" ID aluminum tube and modify a fill adapter (like the one I had for my Condor) into a bushing.Since I have a couple of CO2 tank top adapters, I was going to use one of them.But those threads are not the same as the Edge tank's.The OD of the Edge tank threads are 0.850" and the PB tanks are 0.820"So does anyone know what the 0.850 diameter corresponds to?