I have one of e each, and Mike Chavka's (new within the last two weeks) has a second set screw in it. That screw comes up from the bottom (thru the clearance groove for the pump arm) and secures the barrel. I have a BFD band in brass that does not have this screw, nor the hole for it.
My brass band is from ebay, so it may be earlier BFD production, or it may be that the second screw is just too hard to machine into brass, or... In either case, mine are different, and I like the idea of the barrel being held by a set screw. Of course there are others that like the barrel to float free...
I'm glad to have them both; expensive but very very nice.