Eames Prototype ETR?  

and for reference to the...
and for reference to the original listing in CT...
http://www.liveauctioneers.com/item/22244766_eames-era-surfboard-cocktai...

It Always
amuses me that they use the term 'private collection' to add gravitas.
We all have private collections, surely?

I agree...
That the edge is the giveaway.
Has to be a fake. The honest use and strength of plywood, as well as the celebration of the exposed plywood edge make it really hard to understand why they would use particle board. Not only weaker, but uglier at the edge.
(Unless it was BEFORE the ply?)
Eames did do a half black/ half white combo table, but it was rectangular. Perhaps that is why someone fell for this. (Or was inspired to knock it off?)

Horrendous
either way

I blame Ray.
.

My assessment
its just a cheap ass old board some old horny dude put together in his garage.

!
Bahahahahahaha.

If I were making a
study prototype, I might not waste a piece of expensive material on it. Particle board might be just the ticket. This design looks to me like a sketch, one of many possible novel forms (and not a particularly convincing one). What if there were a whole set of such mock-ups, made at the same time -- and this is the one that survived to gain our attention (and line someone's pocket) ?

Just to be different
I like it. No comment on whether it is or not what it claims to be. The edge has the same paint issues as my Saarinen dining table, so I am not phased by it or seeing it as necessarily cheap. I actually hope it is what is claimed. It would look nice in front the Eames wire sofa that was never produced I think.

I was thinking the edge...
I was thinking the edge looked similar to a Saarinen table's knife edge profile. However, if this were a mock-up I have my doubts that it would have ended up in CT. Most of the prototypes that have popped up are usually around where they were produced or have been previously owned by HM employee. Not, from a private Connecticut Collection.
Also, without any proof that it is in fact authentic, I think it in no way should be advertised as such.
Though, if it does sell for $5,000 or even the starting price of $1500 I'm going to be kicking myself for not buying it when I had the chance...

SDR
Good points. When you think of it as a 3-D "sketch", and consider that there might have been a few different versions, just so they could see them beyond the drawing stage, then it becomes more logical.
I myself have filled many a sketchbook full of godawful shapes that were ultimately discarded-- so why not a full size "sketch" just to get a sense of the feel and presence of a piece?
And my plywood edge comment above is easily refuted once the top is painted in black and white.
It IS a strange and gangly shape, and I can see why it didn't go further, but I like your observations about what is possible.
I find myself wondering how it would look under my black and white Kite clock, with the diagonal and the shaped angles.

No sale.
No sale.

I think that's that.
I think that's that.

And then
there's this thing...