the air dielectric

I don't know what the first company was that used a nearly 100% air dielectric in their cables.  Slinkylinks appears to have been doing this all of 20 years ago.  These days, Inakustik stands out to me for the explicitness and full depiction of their careful internal construction.  Something that Skogrand doesn't do.  At the more inexpensive end of the scale, Black Cat Coppertone Flatwave has found a way of implementing this nearly as well but with a lot lower manufacturing costs.

Other brands claim an air dielectric (e.g. DH Labs) but I have yet to see photographic proof.

Who else is really using an air dielectric these days?

Tara Labs using a vacuum dielectric. Nordost and Harmonic Technology use air. I'm waiting for someone to use sodium hexaflouride. This gas absolutely will not let electrons pass through it, is non-toxic and inexpensive. sounds worthy of interest.
I was going to say Darwin as well. Their ICs are primarily air since the gauge of the silver wire used is so small that it permits only a fraction of the wire's circumference area to make contact with the tubing at any time.

All the best,
@dweller - I think it is sulfer hexafluoride that is commonly used as an electrical dielectric. It would seem this would be a better choice than air since it would prevent oxidation of conductors, but would require that the cables be completely sealed. 
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That the cable must be completely sealed, has also been the drawback to using a vacuum.      That's harder to accomplish, than it sounds.
 @jaytor - Thanks for the correction. Though both are excellent dielectrics, it was sulfer hexafluoride I was thinking of.
Tara Labs claims a vacuum dialectric? Sounds next to impossible to implement correctly. 

Also Inakustik uses a coating which isnt air (as suggested by another member) but it seems a good approach and their cables sound very very good. 
This was 15-20 years ago, Not sure Tara making them now. Cost in the 15K range. Vaccum  had to be refreshed every so often. Probably stopped making (for general public) due to PITA factor and lack of demand. 
The electrons are obfuscating the detail in my music! I need more air in my cables!
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