Coupling Banana Plugs

Well I think I can answer my own question.
I just purchased a couple of banana jacks that are designed to go into a in wall type box.
One side accepts a banana and the other side is designed for bare wire , but it can accept a banana. That side has a set screw for the bare wire but it can also be used for tightening and locking the banana in place. I cut out the plastic that surrounds it.
Looks pretty cool and functions perfectly.

Monster used to have a model banana plug called the Exterminator that had a hole on its rear to piggyback another banana plug.I still have some,but they aren't for sale.

You can stack most banana plugs. Check out Parts Express.
https://www.parts-express.com/parts-express-gold-dual-banana-plug-black--091-334

Yes, but the cables I am using already have banana's attached on each end. So stacking is not an option.

What I seek is a coupler. Sort of like a RCA coupler that is used to connect 2 RCA's together, but made for banana's.

My DIY version does fit the bill, but I am surprised that there really is no commercially made product.

"04-20-15: Denman
Monster used to have a model banana plug called the Exterminator that had a hole on its rear to piggyback another banana plug.I still have some,but they aren't for sale."

They still make connectors like that but they won't work in this case. Both ends need to be female.