I bought a 2x123 flared tube last week, put a flat tailcap on it and really like it. /ubbthreads/images/graemlins/happy14.gif I'm going to drill and tap (#6-32) the flared part of the tube so I can attach one of McGizmo's swivel buttons.
When I first saw the flared tubes I incorrectly assumed that one of the reasons the tube would work nicely with the flat tailcap (and other non-standard versions) was that it was tapped for the swivel button. /ubbthreads/images/graemlins/confused.gif I have three standard Aleph tailcaps all with swivels and they are a great way to carry my flashlights. I even replaced the nut/set screw in the grip ring on my Streamlight NF-2 with a #6-32 nut and a 3/8" long set screw and screwed on a button swivel. It's a much more secure and comfortable than the belt clip that came on it.
It would be nice if they already came tapped for that purpose, but I guess that would add to the cost and maybe some don't like having the extra hole if it's not going to be used. /ubbthreads/images/graemlins/icon3.gif