Had a DIY project done (not by myself). basically got all major brand headphone cables and adapters done with this wire. went with adapter approach as these wires can get very expensive and can't afford to go with all 8 braids full length..
I sourced all components in China, and commissioned a cable maker there who I have dealt with many times for years to do the soldering. I have good reasons to believe the wire's manufacturer is the source for several well known brand names, but can't be certain for 100%.
For the copper one:
each wire consists about 500 strands 7n occ copper (they also call it single crystal OCC, not sure if its a thing). For a 4 wire braid, its get pretty thick for IEM but look and sound great!
All strands are individually insulated but not sure about which type of Litz geometry is used.
Last picture has the PW NO.5 on the left for comparison (im not saying they made PW's wires...i just happen to have this cable at hand).
For the silver one:
8 wire round braid (paid more for an extra dense braid)
each wire consists about 100 strands 7n (not sure if this is true) OCC pure silver.
I am unsure if the strands are insulated individually.
can't wait testing them out more thoroughly.
P.S:
bad choice on the IEM cable slider on my part.. the cables are too thick, they can barely slide..not without risk damaging the jacket. well..never use them anyway, a shinny button would not hurt.