Florence Knoll sideboard  

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Mine seems to have no label... but it has a finished back, so possibly those models weren't labeled.

I have seen them with and wit...
I have seen them with and without paper labels like the one below.

I picked on of these up one...
I picked one of these up, the 4 ft size just last week.
Found it at the local thrift store and basically stole it for $19.91 (i know, weird price huh)!!
It had the Knoll tag underneath (albeit a little bit scratched up, still there) and a date stamp inside the upper right side.
The lock was locked with no key, but nothing a half hour, a bobby pin, and a nail file could't fix.

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My local Amvet's thrift store also prices their items similar ($19.91..0r $13.31 or even $2.62..etc.) so that dishonest people don't dare erase the first digit before bringing the treasure up to the register. All prices are the same when reading them front to back.
ps. what a good deal on the credenza!!