I have 8 beat up Herman Miller stacking bases (sold shells). There is not much of a market for the stacking bases so I decided to just removed the nylon glides and sell those on ebay. I have taken a few out but they don't match the other nylon glides that I have that are typically sold as replacements. Installed they are identical but the part that is inside the metal tube is different. These glides do not have ridges on the nylon that sticks within the metal tube of the legs and the metal part of the glides is different (it is not visible on top of the glide but is recessed inside the top half of the glide. See photos with both types of glides.
Were these glides made by Herman Miller? And if so should I avoid selling them as replacement glide for tubular eames bases (hbase, stacking, dcm/lcm)? 
<img class="wpforo-default
Glides are complete
The glides I removed from the stacking bases are complete. They did not break when i removed them.
These never were like the other glides(with the metal tabs). Also I had a h-base missing two glides so I installed these no problem. They fit tightly into the tubes. And once installed they appear identical.
These are either an earlier version of the glides or are not made by herman miller. So I figured this forum would let me know which.
update
So I had another h-base that was missing a glide. But these mystery glides were not tight enough and could be pulled out easily by hand.
I have reason to believe that both the stacking bases I have and first h-base from my previous post are very old (late 50's). But the second H-base is not so old.
So I am guessing that these are early versions of the glides that got replaced with the metal tab versions. But someone on this forum is sure to know if my guess is right and now I am very curious. But either way I don't think I can sell these, so I have plenty of spares.
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