acetylene tank fitting? new torch won't fit

[crosby]

hi guys. I blew a regulator on my old acetylene torch, and got a new set for my birthday (Chicago Electric). It's Chinese, but it will work for me. I saw a Harris set at Lowes, but that was $175, I paid $100 for mine with blockback protectors. Anyhow, I can't hook up the acetylene regulator because my acetylene tank has a male fitting (the valve on the top of the tank) and so does my acetylene regulator. I checked out the nice Harris set at Lowes, and it has the same fitting. Is there supposed to be some sort of adapter between the tank valve and the regulator? Or do I have an old tank, and they're different now? I guess I will have to take the tank and the regulator to Merriam Graves when I can get up there. Thanks very much for any help guys!!