Weird Shell chairs? Anyone Know the designer?  

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click the box if u cant see the image.

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post the "direct link" URL if u want me to see the image.

I do...
i do post it but it never works, ive tried everything!

probably
Shamrock Plastics Co in Minneapolis, MN
similar looking chair on etsy
http://www.etsy.com/listing/71817178/mid-century-modern-eames-style-shel...

thanks JDIP
that has to be it, they look identical where the legs meet up with the plastic. actually very well designed I would say.

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Sam Avedon, for the win....found a couple of these, one in white and one in peach [armless versions], on a trash day in rural PA...but ours are made by Aladdin Plastics and are just that --plastic....below is patent info...has to be the same chairs..ours has that little cross-hair support underneath as well....
http://www.google.com/patents?id=8G5yAAAAEBAJ&pg=PA1&lpg=PA1&dq=patent+D...

Sam Avedon, but..
Matty is right,
the usual attribution is Sam Avedon. They were made in the US by Alladin Plastics, Gardena/CA (a few blocks away from old Zenith). There´s however an earlier French patent filing for the design (US Pat. 3.032.075, it´s on Google Patents as well). The chair had been some co-op between Avisun (a PP-manufacturer), Alladin and French firm Plaxico. A quite extensive source in Modern Plastics, Vol. 40 (1962/63), May 1963, pp. 90f; 173 f (cont.).
What´s really interesting about the model: It´s not fiberglass, but polypropylene - a very, very early PP shell, made at a time, when it was virtually impossible yet to handle the material, molding such huge pieces.
The chair had been marketed as "Imperial" and "Form-Fit Chair"; there´s a whole series in different shells and bases.
Much neglected milestone in plastic chair evolution from an industrial history point of view..
If anyone happens to have more detailed first-hand knowledge about Sam Avedon and the story, I´d be happy if you get in touch.
Jens
jens.thiel // gmail.com
http://www.functionalfate.org

What years were these made?
I found 2 at a thrift store. Both in grey. One has arms, but no Aladin Plastics stamp underneath. The other is armless, with the stamp. Both are very scratched. Some shallow chunks of material missing, and it looks like fiberglass under the top coat of "plastic". So this is pp? The good areas almost have a subtle leather embossed look in the grey plastic. We are going to repair the chunks before painting them with plastic adhering paint. Can't fix the scratches, even rubbing out doesn't help.
I'd love to know what years these would have been made. They look pretty old to me.