I got a female coupling and piece of threaded rod. It's a tough size to find but I found it at Fastenal....1/4-28.
I also bought a piece of 1" dowl from home depot.
**EDIT** Moke has discovered that a piece of 1/2" pvc does the trick instead of the dowl....no drilling needed!
I cut the dowl 8" long using a circular saw. (a table saw would have been better).
I then screwed the female coupling to the top of the a27 bar and threaded my piece of rod into the other end.