Saarinen / Knoll chair question  

Model 44 Chair?
In 1946 Florence Knoll designed a very similar looking chair for her early office collection that has the solid back. The Model 44 had wood legs; Model 45 was on a 4-star base with swivel mechanism. Could this be what you have?

Pics
Thank you, ankh1980. The base is neither wooden or a star base. I've added some photos of the chair, including the Knoll label. (The cushion is pretty flat from age, and it should be recovered.)

Label
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Woodywood!
It Seems Woodywood already answered this question for someone else in '09. Still, I'd love to know how I can determine the dates of production.
http://www.designaddict.com/design_addict/forums/index.cfm/fuseaction/th...

Rare
Wow... looks like you have a very rare chair there, it's certainly a Saarinen. Lucky you!

Yeah
I'm not sure exactly when the full-back version was produced (and when it was discontinued). Perhaps someone with Knoll reference material can help. I would imagine that the full-back version was designed around the same time and was probably eventually discontinued because it was a less popular variation. Personally, I think it looks beautiful.

Dates
Well Knoll Associates became Knoll International in 1969; and were at 320 Park Avenue until the early 70's... so I would say the chair is 40 years old.

Thank you
Woodywood, I think they're beautiful too. I find the more common version to have a little more flex and padding, and consequently be slightly more comfortable. But I do love the chair, and look forward to having it recovered.
Ankh1980, thank you so much for your good detective work! I didn't think about tracing the address and name change. I'm glad to be able to put a general date to its production.

Cameo
I was watching Mad Men today (season one) and noticed that all the Knoll chairs around a table in the main office have solid backs like this. I wonder if the solid back version was at one time more popular in office settings.
I also noticed that the Eames management chairs in the show have five-star bases. Were those not introduced until later? I have a couple from as recently as 1983 that have the four-star bases.

Yes
The Pollock chairs also switched to 5-star base in recent years, presumably due to safety requirements.