I recently purchased a vintage 36" round Eames table that has an aluminum base that doesn't look like three design variations I'm familiar with. It's definitely Herman Miller, as it had the original round metal decal underneath the table top.
Any info as to what model this particular base is and the year(s) of production would be helpful. Thanks. 
<img class="wpforo-default-image-attachment wpforoimg" src=" http://old.designaddict.com/sites/default/files/foru 
Early "universal" base
... as seen on Time Life chairs.
They later extended the foot. Do a google search of Time Life chairs and you will see both variations. They used the same base design for tables and chairs. The more common version you will see on aluminum group chairs as well as table bases.
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