It does indeed look as if they are unextruded cola bottles

I received one of those PET preforms nearly 25 years ago on a tour through a plastics manufacturing facility. It was an un-extruded 2 liter Mountain Dew bottle. I wish I knew where it was, because it seems like it would be easy to DIY a lanyard carrier for it.

The ones in the Keep-2-Go pictures look shorter than the one I had, so they might be unextruded 1 liter bottles. It's been so long though I could be mistaken.
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