These are quite the strange units. Here is the story that I was told from the guy I got them from in my package deal..
Many of you may or may not know Dale Laroche. He has been restoring Pop Machines for Many Many Years... Anyways... I have known him for a while and he is the one that I recently bought all these machines from, 10 81's 2 vmc 27s, 2 39's and 2 sliders plus many parts, and some extra compressors including these two.

He said they where from an experimental coke machine that Coke was playing around with and consulted with him on the design, and they actually had a working unit at one of the Coke Conventions years ago (late 90's I think he said) it was a barrel looking unit, sat on the floor and was about 5 feet tall, Made with a lot of plexiglass so you could see the vending unit of the machine and the cans inside. the cans where near the top side, hence why the cooling condensors are soo high up. the cans rolled down and around in a spiral toward the vending door. not sure much more than that, or how it worked or how many selections... he didn't have any photos of the unit. when they scrapped the unit he knew the guy at Midwest Coca-Cola that was in charge of the project and he was given the compressors, figuring he could use them for something else. we'll now they sit in my garage with maybe hopes of reusing them someday? we'll see.

I have had a good time talking and meeting with Dale over the last few months as we finalized our transaction... .TONS OF STORIES, from teh early chicago show days to the Coke Conventions the history on some machines and to hear about the machines that he has found over the years including TWO of the Originial VENDO DECAPPERS that are supposably known to exist, Dale found them originally and had one working at his house back in early 90s'.  This guy knows who to restore machines too,,,, nothing left untouched... they are works of art when done. Some of the mods and he has done are really cool as well... like RT56's with lighted doors and Medallions in the door, to Pepsi 56 litups and just about everthing you can imagine he has worked on ... I think he told me something like 200 machines he's done... I only hope to be able to produce work like that.