help identifying a set of shell chairs  

That is
A knock-off of Saarinen's Tulip side chair.

interesting....on the...
interesting....on the underside does it look like this would have been the original base for these (it doesn't look like the seat sits flush)?

image of base...
The base doesn't sit flush. I've attached an additional photo that might help...
http://1.bp.blogspot.com/_B64XUIhzc4c/Sl0D2DANWkI/AAAAAAAAAUg/j_SSIUpLmH...
The swivel portion on all the chairs is very rusty. However, the bases are quite heavy and good quality.
if you know of any information year, make etc.
thank you!
http://1.bp.blogspot.com/_B64XUIhzc4c/Sl0D2DANWkI/AAAAAAAAAUg/j_SSIUpLmH...